We should start a "TriStar Only" club. (just kidding)
I bought my '89 TriStar 190 exactly one year ago, it had 221 hours. It was a garage queen, sat unused for years as it was part of a divorce settlement. The husband didn't want it, and the wife didn't ski. Go figure. The hull needed a little vinegar, and the interior needed detailing. It looks new now; lack of sun exposure helps with that The interior is all original.
My sweat equity included: detailing, remount the windshield with new foam weatherstripping, replacing the driver seat slider, rebuilding the coaming panels (so that a ski would fit), replace the plastic bilge pump outlet with stainless, new tires, replace/repair the trailer lights, rewire the light plug, install LED lights under the gunwales, rewire the stereo, and other odds and ends.
I'd agree with all the comments above. It has a pretty good, not great slalom wake. Since I'm a pretty good but not great slalom skier it works for me. I can't comment on the boarding wake.
It could use more room, there's very little storage. Any more than three to four people gets uncomfortable for skiing. I usually take the back seat out to get extra floor space.
If anyone rides up front they're likely to get wet, especially if the driver is careless and noses into a wake.