It uses the same chip and display as the RG34XXSP, and it looks like the only functional differences are all downsides. You don’t get sticks and the screen is also a bit dimmer/less saturated, despite on paper being the same spec, and there is also less RAM. Being a newer device, it’s also more expensive too.
The other differences seem to be aesthetic, the metallicy finish is neat, but the colours are not nearly as interesting as the GC purple, Pikachu yellow, or deep blue. You also have less forehead in favour of a chin as well.
It’s kind of neat if you want an alternative with no sticks, but the higher price for an effectively identical product isn’t great.
R36S can do the same (PS1, most N64, and even some PSP and Dreamcast) in a DMG form factor for like $30ish USD shipped right now. There is also the R36H if you prefer horizontal form factor for about the same price. I think it uses the same chip.
R36S, R36H, and the ones mentioned by OP are not FPGA though.