I think an 1100 is more useful than an 800, but I use my 500 a lot too.
One could attach it to a square and use it to lop 4x2s, which is what I do with another short rail piece.
I cut mine with a jig saw.
Ideally you know someone with a milling machine and they square the end, but as the ends should not touch when joined maybe that is a waste. In any case I did my cut and was going to take to it with a file... But I just knocked off a couple of burrs and it has worked well.
I was a Bosch rail, but the principles seem the same.
I used a Bosch metal blade.
Maybe a track saw on slow would work better... It is aluminium so it was like butter for the jig saw. I ended up cutting a bunch of Ikea curtain rails that way (alloy) and plumbing plastic pipe as it is easier that way.