Nintendo DS I think have more stylus heavy games than the 3DS, and the DSi is still pretty reasonable in price. So I think getting a DSi is worth it. And seems to go around the price of a new triple A title and is easy to mod. There’s open source flash carts like the DSpico available, and a DS Pico with IR and PicoWalker said to be coming out too so you don’t have to get the official pokewalker and Pokemon cartridge. Those Pokemon cartridges are insane in value so it’ll be nice when the DSPico IR version is available for those wanting to utilize pokewalker with it.

If you are just playing Pokemon than stylus responsiveness doesn’t matter much, but if you are planning to play stylus heavy games then I think the actual DS is the route to go. DSi XL has the best screen among the DS line with it being dual IPS.

3DS can play 3DS and DS games, but those are like double to triple the price.