I've got a Reverb and really rate it but I'd bever pay full price for it. I bought mine cheap from Wiggle at the start of the year and its been great so far. I run my lever under the bar to offer it some protection from knocks and crashes - it feels liek it is in the perfect place where my left hand shifter used to be.
I've only bled it once and it was a piece of cake and it didn't really need it but whilst I was faffing with the hose length it seemed like a good idea. My only issue with it is the cost of spares.
The Thomson looks pretty nice and all of my Thomson stuff has been flawless.
A demo bike I rode had a Lev and I wasn't sold on it - the fixed cable entry point is great but I don't think that the lever action felt as smooth as it did on my Reverb. I couldn't get on with the lever being part of the grip either because it was too close.
I think though we have got to the point where if you but a KS or a Reverb you'll get a pretty sound post.