darkglass vintage is probably your best bet for vintage OD. havent had it but ive had a b3k and the build quality/sound was excellent, i'd trust anything they put out sounds fantastic.
personally I was not a big fan of the MP BBBOD or Catalinbread SFT. SFT was too "wooly" for me, everything seemed hairy but lacked definition (unlike my ampeg...). BBBOD I cant really recall but I didnt like it paired with my GK MB500. Im sure the fusion sounds different than the MB, but I really liked the green rhino or your TS of choice. TS based pedals seem like a natural extension to GK amps and their boost circuit to me. I wouldnt consider them too warm though.
Empress Germ Drive (or Multidrive but $$) - multidrive isnt really a warm vintage od, made for combining OD, DIST, and Fuzz for unique distorted tones.
Barber Small Fry - havent tried, but I have tried the LTD SR. Barber is wholly underrated, and though not warm, the LTD SR is one of the more transparent OD's Ive tried even without a blend, and designed for guitar.
Wren & Cuff Phat Phuk or Mercy Phuk - phat phuk b is an awesome full sounding boost, and will push tubes into a beautiful breakup, but like I said its full sounding and not particularly warm. Mercy phuk seems to have too much low end loss for my taste.
(sfx) Micro Red Dragon - havent tried
Wounded Paw Black Sheep - an OD I would love to get my hands on. Versatile, should be able to nail most sounds you want with this.
Wampler Ecstasy Drive - clips on johnk's website
http://johnkvintageguitars.homestead.com/Overdrive-Pedals.html
JHS Boost (can't remember the name of the pedal) - Although the Low drive did intrigue me at one point, I probably wouldnt ever buy JHS due to their previous (and possibly currently) blatant use of exact circuits sold as their own takes on pedals. Go for it if you want to though!
do a lot of listening through JohnK's website that i linked. You can find most of those pedals used here or on thegearpage, and if you dont like it flip it. The trouble/hassle is worth it to find to find the perfect sound IMO