I have a p1s it's pretty good and don't really feel a need to get the X1 or the newest one

I would recommend a bambu printer. They really are no hassle and reliable.

So for FDM, I want a flat surface on bottom so it adheres to the print bed and less than 45 degree overhangs across the the model. But for Resin printing, you don't really want the large flat areas because it will have suction forces and be prone to warping and more failures.