Hi Sekhmet, Dendrobium unicum is one of my absolute favorite species, it's pretty easy to grow and has gorgeous flowers with nice fragrance. My small one is in bud right now, I'll post some pictures in a week or two assuming they don't blast.
The only really tricky thing with this type of Den. is the strong seasonality they prefer. When the weather is warm they want to be fed heavily and kept almost constantly moist, and when it's cool they should be kept much drier (I water about once per week throughout the winter) and not fertilized. Bright light should be provided year-round, in the natural habitat it's probably somewhat brighter in winter due to host trees being deciduous. Cool temps seem to be the most important bloom cue, I give mine nighttime temps in the high 50s from about mid-November to mid-March and I've gotten nice blooms for the past few years.
These do very well mounted or tightly potted. When I pot this type of Den I'm currently using small terracotta pots with nothing but sphagnum and styrofoam peanuts, packed pretty tight but in such a way that the pots drain very fast. Any free-draining epiphyte mix should work fine, though.
Oak Hill is a very good nursery, I've never had any problems with plants from them. Andy's also has a great reputation though I have no firsthand experience, but I don't think you'll go wrong with either place.
Happy Birthday in advance!
--Nat