I just use a cheap, old HP Laserjet 1020.
I think pretty much toner is toner.
You can go into printer setup advanced settings, and maximize the amount of toner put out on some drivers. I haven't really found that necessary.
The secret to getting good results is getting the enclosure absolutely (sanded) flat, and clean. I wipe down my enclosures with acetone a few minutes before I iron on the transfer.
Edit: Meaning, don't touch it with your fingers after you clean it.. the oils from your hand can keep the toner from sticking I've found.
MC