OK,so i went and got the JC10 compressor.Received it last Friday.It is to replace the SENCO PC 1010 little compressor that i have been using for the past 6 years.
I got to use it today and really like this new addition.For those of you who has the Senco and thinking about the Rol-air,here is what you need to know.
It is a little bigger.2.3 gallons vs 1
It is heavier,but easy to carry.
The JC10 has 2 pistons,nice design,really fast pumping that air.Rated 1 hp ,7amps motor.
When totally empty,JC10 takes 45s to fill.The Senco 2 min 20 s
Recovery,JC10 12s  - Senco 40s
A lot faster!  The JC10 was able to keep up with my 15g nailer.My Senco not so much,i would get about 5 shots and then it just keep on going and going....Many times,i have to wait for it to get enought psi.
But one thing i really like about the JC10 is how quite it is.    VERY QUITE!
Nice compressor,i think this will be just fine for what i do.For continuous production trim work i can't say much about.I don't do that much trim work.Only time will tell if this compressor will last.I hope so.

I have the Senco and that's about how I thought they'd compare.  I like my Senco but I'd use it a lot more if it was equal to the Rol-air.  Thanks for the side by side comparison.

Wow I never realized how long it took for the senco to fill.  I was thinking about getting the senco but glad I decided on the JC10.  I've been abusing my JC10 to see how it holds up.  Just today me and my helper were running 2 brad guns off of it and it did fine, it ran a lot though.  The jc10's recovery time is very quick, its easily noticed when I use the blower attachment to blow my tools off at the end of the day.  As long as you don't hold the blower handle all the way open the compressor keeps up surprisingly well.

Dave

I think it is quiter!
As far as size here's what the owner's manual says;15 5/8"L   16 3/4"W    14 3/4"H

In a way you confirmed my point, even though you misunderstood what I meant.  Of course they are both compressors and both are used to supply air to nail guns, but I meant that there are some nailing jobs where the Senco would be ideal because of it's smaller size and lighter weight, when the air output and recovery time aren't too important.

I'm sure there are plenty of users that will be very happy with the Rolair by itself, but some people like me go on jobs sometimes where conditions preclude getting a bigger compressor up 3 floors, the last of which is a 60 degree inclined, 28 inch wide staircase with no hand rails or maybe there's only a little bit of trim work to do.  Maybe a CO2 bottle setup and the Rolair is best for you.  Maybe hand nailing everything makes you happy.  I don't know, but these are just some examples.  As always, you have to figure out what works for you after sorting through all of the advice.

I'm not knocking either compressor.  I just think there are times when one would be more appropriate than the other.

No problem, Brice.  The JC10 isn't near the small size of the PC1010 and about twice the weight. The JC10 is more comparable in size to the Senco PC0968.

Well,it's been a couple weeks since i got the JC10 compressor and i have been very happy with it so far.
I have not had to wait for it when using my 15g and no nails sticking out.
So going from the senco to this,i have to say that i do feel it in the weight.Not so bad but do miss that light weight Senco
It is the perfect size for what i do but if you are a trim carpenter and do production trimwork, i don't think i would invest into the JC10 for that kind of work.I would look at something bigger(bigger tank)I do have a DeWalt 4g. (made by Emglo)that i would use if i ever have a big job that require  production nailling.

Keep in mind that when you raise the pressure setting to 100 psi or anything higher than the factory setting (AND you haven't messed with the differential pressure adjustment - difference between stop and start pressures), you will raise the stop pressure setting as well and that can approach the safety release valve's pressure setting causing it to constantly or occasionally blow off.  While I can't advise anyone to replace the factory safety valve with another that has a higher pressure setting, that is an option should your current valve trigger after you've changed the pressure setting on the pressure switch.  There is a tolerance to the safety valves, so sometimes it will blow off and other times it won't depending on how close you've got the maximum pressure set at.

Example - safety valve says 140 psi.  Compressor set to come on at 90 psi and shut off at 125 psi.  You adjust the pressure switch so now the compressor kicks on at 100 psi and shuts off at 135 psi.  It's very close to the 140 psi stamped on the safety valve.  You might trigger the valve.  The manufacturer designs the safety valve knowing the quality of the parts they've used and the tank itself.  You might have lower quality parts or maybe bad tank welds that could become dangerous should you raise the pressure or change out the safety valve to a higher one.

Hope the info helps.

Resetting the pressure to recharge the compressor at 100 psi and setting the regulator for something slightly less, like 95 psi allows the compressor to keep up with the nail gun using 95 psi of air.  If the regulator were set at 95 psi and the pressure switch was set at 90 psi, the nailer wouldn't set the nails fully when the tank pressure drops below 95 psi, until the compressor hits 90, turns on and charges the tank back up again.  Having the regulator set lower than the pressure switch allows it to keep up with your nail gun or whatever else is connected (assuming the SCFM rating of the compressor is above the connected tool's SCFM rating).

And yes Nick, that causes the compressor to turn on more frequently.

This is the JC10 or the PC1010 you're talking about? I've just ordered a PC1010 for myself because of its quietness, size and easy portability. If I can get it to attain 120 psi without it  running constantly, then it will fill all my current needs.

I have the Senco 1010 and do not have the Rolair jc10 so my comments are restricted to the Senco.

On mine, the pressure set screws seemed to adjust the pressure when the compressor cycled on and when it cycled off.

The Rolair sounds like a smaller version of the 4 gallon Thomas compressor I have - dual compression pistons running off one motor.  My only gripe is I wish Thomas would use higher pressure compressor - 150 or 175 or even 200 psi instead of just 125.

That's what I had said (post #10).  

Oh sorry…Great minds think alike lol. Well I agree with you haha.

The Rol-air JC10 is very quiet and has great recovery.  It’s a fantastic unit.   If you want something smaller I would recommend the Bostitch  CAP-1512.  Just as light as the Senco 1010 but with much quicker recovery.  I used it all the time for a small, mobile, light weight compressor.  It will even run a framer if needed.

http://www.amazon.com/Bostitch-Gallon-High-Output-Compressor-CAP1512/dp/B004285RLS

Your probably not going to be able to compare that way.  The specs on dB vary acording to things like distance from the source while testing, where it was tested, the operator and equipment testing it, the scale that was used for testing.  I've looked at dB specs from many manufacturers and they're all over the place and unreliable, I feel.  Best to test at least two models you're interested in, right in front of you or at least get that kind of feedback from others who have.