For stability, the desktop with a PCI card (like a Delta) would be suggested.

Laptops; some people find one card works well, while others find another works well.
M-Audio external units do not play nice with BiaB we are told, but work with Realband.

Some say Tascam units work well for BiaB and RB, others don't care for Tascam support.

I'd stick with the desktop for now if its up to the job, unless you need the mobility.

I do not work here, but the benefits are still awesome
Make your sound your own!