We use sublimation extensively at work. The two companies we deal with are Mega and I-Sub.
The heat press we have is a HT-600. It doesn't have a digital thermometer though so to get the right temperature you have to turn a dial and use a bit of guesswork. As I understand it, this is because ours is an old model and newer ones are all digital and you type in the temperature and it does the rest.
We also have two Jarin HF2200 mug presses. I don't know how much they cost but I would certainly recommend them.
What printer would you be using? For a few years we used an Epson 1290 but have just bought an R1800 with sublimation kit. We're having some problems getting accurate colour reproduction with this on different surfaces. I'm quite demanding about this so we'll be getting Printfix Pro to generate profiles for the different items we use rather than the generic profile that came with the sub kit.
Hope this helps.
70-300 APO Super Macro II, Sigma 12-24, Speedlite 430EX, EF-S 18-55, ...