I recently purchased a C12, and I've been pretty happy with it. I also have the Makita 18v LXT cordless tools, and I count on those more for larger rough-framing duties. I bought the C12 as more of a go-to, lightweight drill for trim-out duties such as cabinet construction and installation, as well as installing door handles, etc, where my Makita drill is too big and bulky, and my impact driver had too much torque. So, for, say, framing a deck I'm more likely to rely on my Makita stuff, whereas I'm counting on my C12 for more finesse applications, though I recently used it with the depth-stop chuck to screw-out a cedar deck using 2.5" screws, and so long as I was conscious about immediately charging spent batteries I never was left without a charged battery.
Something to keep in mind as far as batteries go is there are three different Ah options, 1.3, 2.4, and 3.0. I bought the 1.3Ah to keep weight down, knowing that the batteries will have to be charged more often. Ideally, I like the idea of buying the Ni-MH batteries, but their poor performance in Minnesota winters have discouraged me.
Frank, regarding your batteries having to be rebuilt after 3 years, I know it sounds sad but I was chatting with the GM at 7 Corners Ace Hardware the other day about tool batteries and he claimed that, regardless of frequency of usage, that most power tool batteries are pretty much useless after 2-4 years. My Makita LXT batteries wouldn't charge after roughly 2.5 years (hard use, 6+ days a week), but my local retailer simply warrantied them out and simply gave me two new batteries and later a charger right off the wall. Likewise, as much as I'd like to think otherwise, I don't really expect to get more than 2 years of life from my C12 batteries, and will just pro-rate the purchase of new packs into my bids.
