I've read good reviews about M Tech in this page so I decided to take my (for me) brand new 2003 e46 325i... I wasn't disappointed. The first thing I made was an oil and filter change and an overall inspection of the car ($100). They were really fast and I think honest with me, so I took it for the second time to fix some important things they told me needed to be fixed in a short time (replaced left front tie rod assembly, both sides rear shocks and mounts and a wheel alignment) I took the car in the morning at in the same day it was ready and the price was really good (considering it's a BMW).
Also, I was aware of the cooling system since I've read it's a weak part of this models. They had no problem on taking a look at the coolant level, the working temperature and explaining me a little on how does the system works (and also they told me to give them a call If I saw something wrong). So as far as I own this car I will be visiting them anytime I need to.