For occasional use, I like my Spin Doctor truing stand.
I bought it 7 or 8 years ago. I've build a few wheels from scratch, cleaned up the inconsistent tension on a couple of cheap spare wheels, and made occasional minor truing adjustments.
The axle support arms are self-centering, quite accurately. I have to (lightly) clamp the wheel with a quick release, though. As a double check, when I'm done, I can put the wheel on the bike, adjust the brakes for even gaps on both sides, then flip the wheel and it's still centered correctly between the pads.
I like how the feeler gauges can be twisted and pushed into the rim individually. I'll determine which side needs the biggest adjustment, and just use that feeler. I use the sound of the feeler rubbing the high spot to determine exactly where the rim is out of true.
It's pretty sturdy for an aluminum and plastic tool. I don't build a lot of wheels, but I do fine tune my wheels occasionally. It's held up great. I'm pretty picky about side-to-side true, and I can get the wheel very even.
Once my good wheels are true, and the spoke are as evenly tensioned as possible, I rarely have to touch up the truing, even after big pothole hits. So I don't need to use it very often, but it's very nice to have one for the occasional minor adjustments, even ones that aren't annoying enough to take it into a shop. It's nice to get the last bit of faint brake pulsing out of the wheel.
I have a tiny crack at one spoke hole, due to a couple of big pothole hits last winter. (due to night group rides that didn't call out the holes, grrr) I'll be replacing the rim later this summer.
A one-sided stand, like the TS-8, would drive me crazy. I spin the wheel, slide in both feelers, then see which side has the highest spot. Working on just that side, I'll reduce that high spot, then recheck both sides. Often, the next highest spot is on the other side. It would be a lot harder with a single-sided stand.
If your son plans to build wheels, or even fix cheaper wheels that don't have even tension from the factory, a tension meter is really useful
. I don't have the long-term experience
to know how much tension is needed, just by feel. So the tension meter gets the correct tension on the spokes for long wheel life, and it's good for checking for even tension between all the spokes. It's quick and easy to use.
See the Park TM-1