Like several others have mentioned, I have a Martin 0X which sounds great. I don’t know how durable the HPL is, but at least I don’t have to worry about temperature. I also have a Bruko soprano which feels very durable, also sounds great, and was less expensive than the Martin.
For concerts, I take a Breedlove concert. They’re current/recent offerings are a little overpriced, but if you can find them on sale, I think they make ideal beater/traveler ukes. They sound and feel great. Are slightly overbuilt and so durable, with laminate sides and back. Their models have a little bit of variety on price, but they’re all basically the same thing, with the only differences being onboard electronics, cutaway, and different wood stains. I picked up a new one with no frills on sale for close to $150. I’ll even leave it in the car sometimes if the weather’s not terrible.
I don’t know if anyone else does this, but I have a decent ukulele (a Rebel) that I superficially damaged almost right after I got it. The damage is slight enough that I don’t know if it’s worth repairing. But annoying enough that I basically resigned myself to using it as a nicer traveler without worrying about any dents or scratches it might get. I know some people take their high end ukes camping and to the beach and wherever. But I haven’t felt comfortable doing that myself. The Rebel, however, isn’t super expensive and already had some damage, so that’s my nicer traveler. I don’t know if I would be using it that way if it weren’t for that initial damage.