Long Putters - If you can't beat em, join em

So my buddy bought a long putter off ebay couple weeks ago and I tried it out a bit on the putting green last Saturday.  My goodness, no wonder every player is switching to one these days.  I have always been hesitant in using one just because I have had difficulty with feel any time I've tried one before, but maybe it was just finally using one that was the right length, because now I see how useful they really are.

Buddy told me Dave Love III uses one just for practice, then switches back to his normal short putter for the round.  Haven't done any research on that, but I think he's on to something.  Immediately I could feel the difference between my good/bad strokes with the long putter and started working on finding the same feeling when going back to my regular one.

I've searched ebay a bit and think I'm going to try and find a decent one that's not too expensive also just for practice purposes, but who knows how long it will be before using it full time.  Guess I'm due for a new toy anyways.  Any recommendations?

The stores were bare 6 months ago, a lot of new ones came in, and now there's a good selection of used ones. Buy used.

As for what to buy?  Stick with a name brand so you can unload it if you want to. SF should have some golf supermarkets - I would start there and try a selection.