SteamDeck

It is a bit heavy, if you're holding it up the whole time. I usually use it resting on something (like my lap) if I'm playing for an extended period. It does get a bit hot, too, but not too hot. How hot it would get at your location is hard to say without knowing what the temperatures are like, but it's hotter than a typical handheld.

As to whether it's worth it... this is just my personal opinion, but I think it's the best hand-held gaming device on the market by a huge margin. It's pricey, but you really get what you pay for; it's an enthusiast device, for sure, but the build quality feels great, it's modifiable, both hardware and software, and it runs games fantastically. Strongly recommend.