I use the Matias Mini Tactile Pro with my Mac http://matias.ca/minitactilepro/mac/ . It has custom Matias Click switches that they say emulate the old ALPS switches before ALPS changed hands. It's probably my favorite keyboard that I've ever used, and I'd say that it's a nice middle ground between buckling spring (which can be actually too difficult to use, as evidenced by reports of injuries in this thread) and the softer, less tactile Cherry switches.
I do also have a Rosewill RK-9000BR with Cherry Brown microswitches for my gaming PC, and enjoy that as well.
edit: Also, this thread has taught me about Topre switches, so cool!