I always recommend Tan America and Ergoline for professional reasons. You'll get recommendations from everyone based on their own experience with the equipment they've had or heard about. Just remember the advice here is free, so don't go asking for any refunds if you aren't 100% satisfied with the advice you get.
As for your mix, with an 8 unit salon, I advise (from my default file) to go with four 20 min units(28-32 100w lamps), tWo mid-level (15 min 36-42 lamp w/facials) units, one "OMG this is cool unit!" (12 min, 50+ lamps w/facials and adjustable intensities and fan speeds), and one stand-up (The Sun Capsules tan great, are easy to maintain and repair, and would be a good choice - but not my first).
I can't say this is the perfect mix for you and your unique circumstances, but 9 times out of ten it's not bad shooting from the hip to start out. There are also qualified consultants in the industry that may be of some help to you. Having said that, hope this helps. Good luck! -Belvy