I used (and still do, occasionally) a TLR for a long while and really liked it. When I wanted some more lens choices, I started seeing what was available that I could afford. Used medium format bodies were/are going cheap so that didn't help me pick one. Lenses, on the other hand, were still pricey, even used, for Hassleblad, Mamiya, and Bronica.
I ended up looking at the Kiev cameras--88 and 60--because of the lenses that are available and, frankly, because I didn't have a ton of $ to spend.
Ultimately I bought an ARAX modified Kiev 60. I chose the 60 over the 88 mainly because it is a simpler camera. Since I didn't need changeable backs, I figured the extra complication wasn't worth the
potential for trouble the backs would add.
I chose to deal with ARAX(Gevorg Vartanyan) for a couple of reasons: First, admittedly, his prices were much better than either of the US dealers. Secondly, he was unfalingly helpful and polite when answering the many questions I pestered himw with over the 11 months it took me to save the $ for what I settled on as my kit. And he has been so since then as well.
Bottom line: If you want either the K-88 or the K-60, in my opinion ARAX is who to buy one from.
There is a page of links at the ARAX site that is very useful:
http://www.araxphoto.com/links/
One thing I would change about my lens line up: I got the MIR-26 (45mm wide angle) and have not been happy with it. I think the 50mm Flektagon is probably the better choice in that range.
Rob