The V1 seems weird to spend so much on when the V2 and OLED exist for the same or less money.
Emulating on a Switch is also an odd choice, it's mainly for pirating current games. For €300 you could find a second hand V1 Deck and emulate Switch games instead.
I currently just pirate the roms and play the games through emulation. Wondering whether it is worth it to purchase an V1 Switch, that can be ‘hacked’ and then put the pirate roms into it to play the games handheld (traveling, in bed, cozied up next to the heater).
I have been told only the V1 versions can be hacked/ jailbroken.
Playing roms on a Switch means you're NOT emulating, that's the reason people jailbreak them. Plenty of Switch games run like crap on a Steam Deck, and the more demanding games are difficult to get running at all via emulation.
I'm not saying a jailbroken Switch is the best option, I'm just saying there are pros and cons. Honestly, I'd recommend OP get a cheap desktop PC with a budget GPU instead of a Steam Deck, unless they need it to be portable. It would perform better for emulation.