I have a Matrix console-mounted job that is older than dirt (sea water?) and a Suunto Stinger that is about a year old. I have used the Matrix for quite a while and never had a complaint. Since I carry a camera U/W, I usually tucked the console in my BC or looped over my left arm. Never had a problem.
I got the Stinger because I wanted a back-up since I had actually seen a couple of computers die on trips. Funny thing is that I use them both during dives. The Stinger is more conservative, so I use it on ascents; the Matrix is right next to my air gauge, so I tend to peek at it when I check my air. At other times, I just glance at the Stinger.
If I had to choose only one, what would I do? Probably go with the Stinger: its size and convenience draws me to that conclusion.
An afterthought: Most of our dives are boat dives and we tend to leave our gear on the boat or in a locker. So, I used a Suunto quick release (qr) on my console so I could take just the console back to my room for dive logging. The Stinger obviates the need for that. However, I left the qr on the console because it makes packing the regulator much easier.
Scorpionfish