Not a TriMetric, but for $20 might be worth trying out...
Bayite DC 6.5V-100V Digital ammeter voltmeter Amazon suggested this for me and I'm thinking for $20 I might just give it a try. Has very good reviews too.
Forum Discussion
Yes, I did calibrate them. But they seemed to wander. They are not bad as long as you like to tinker. I just wasn't satisfied.
