I’ve discovered that my rear rim has cracked around two of the nipples, so I need to look at replacing it.
I’d rather not have another 340, but the Alpha 400 looks a little more robust. Then there’s the H+ Archetype, which seems good value with a slight weight penalty over the Stans 400.
Is there anything else I should be considering? Must come in 24 hole.

Do Pacenti do a 24h?
I’ve only built one set so far, but impressed with the quality.
Surprised at your Alpha issue, I’ve done around 4000 miles on mine, built to 1270g for the pair with rev spokes, alloy nipples etc, including 2 Alp & 1 Pyrenees trips & not had any problems, other than the rear is now getting a bit thin!

Pacenti SL23 or SL25 – but they’re a lot more than the H Plus Son rims which are still very good.

It was the SL25’s I built with last week, have to be one of, if not the best road rim I’ve ever built.
The size was the same as claimed & they were road to begin with! Sounds simple, but so many aren’t.

The Pacenti’s look good, buy the SL25 is disc only by the look of it, so the 23 is the only option.

I had a Pacenti SL23 crack round the nipples leading to a spoke pulling through. It was a 28h and spoke tensions weren’t massive.