I joined mountainside last year and as for the facility I'd give it 5 stars. I enjoy the equipment and they recently made some nice upgrades. I was just frustrated how it seems like they gave my pregnant wife the runaround on getting a membership recently which I had to sort out with them as they charged us a higher monthly price than what was agreed to, double charged us for the first month (due to a "glitch") and weren't up front with the up front fee, and paying the first and last months fee first.
I think they could improve on the transparency but everything got sorted out in the end even though it felt like they do this extra charging to a lot of people in hoping that most people don't check their credit/debit card charges.
My tip would be to understand exactly what they are charging and get the statement before giving them your card (don't be in a hurry like we were).
EDIT: Another tip is that the ten free guest passes they allow has to be for a different guess everything (ie your guest can't come twice with you) which isn't transparent on the website at all