My main machine is a computerized Brother my DH bought me for Christmas about 4 years ago. I have had tension trouble twice... both times were from using cheaper thread (I was making Halloween costumes one of those times & cheerleading bags another & didn't want to use my precious quilting thread on such menial items. :lol: ). Well, each time the service guy told me the threads had wrapped around the tension discs on the inside. So, with the $65 I spent each time I had it repaired, I came to realize that not only should I have used good thread, but that money would have bought a whole lot of fabric!!! (& thread :lol: )
I am an avid fan of Brother machines, but they do not play well with lower end threads. For all of my piecing, like Tim, I use silk wrapped cotton Mettler. For quilting, well that depends on the project, but I assure you it is never the cheap stuff... it costs way more in the long run.
Good luck in your decision & congrats on the new job!! :D