I went with skinbase. You rent it for £12.25 a week, first 2 weeks are free. They provide everything you need, marketing material and free training. I've been with them a year in July. They are always sending you marketing maternial, I had 2 weeks just after xmas where I didn't do any microdermbrasion and they rang to see if there was anything they could do to help.
I emailed client's to tell them about the machine and when I will start to do it (the day after my training), and it went really well from day one.
It's a great machine and the result's are good. I think also the pay as you go scheme that they do you are only contracted for 6 months so if you find it doesn't do well you can hand it back and if you haven't made a profit they'll give you your money back.
Kerryx