I own a new, never wet Pinnacle Tempo 3mm. It's not bad, and I'd call it a toss-up between the not as warm but probably better stitched Henderson and it... but it's not fully Merino lined, just the core area, the shoulders and knee pads are
ing jokes, and the stitching and zippers are not impressive. The fit wasn't as good as my Pinnacle M-E suit of the same size, and then I got too busy to return it.
I think the seams on the Henderson are better.
Pinnacle used to be the answer for sure. Now, it's plastic zippers and much less merino lining. On the rare occasion a dive calls for a 3mm or 7mm rather than a lavacore shirt/trunks or a drysuit, I'll dive my Pinnacle M-E suits (fully merino lined from the core all the way to the extremities, real rubber shoulder and kevlar knee pads, and made with brass zippers) until they fall to shreds. The Tempo will sit until I can sell the damn thing, surely at a significant loss.
Somewhere out there, there must be a good wetsuit. Neither Pinnacle nor Henderson makes one these days, however.