So I compared my N3DSXL top screen IPS to both my DSi and DSi XL. As most people already know on both DSi and DSi XL you get a much more crisp screen in comparison to the slightly blurrier 3DS screen as games don’t scale as well on a 3DS screen. In pixel perfect mode there is no blurring on 3DS and is as sharp as DSi
However I noticed some additional things, the colors seem to pop most on DSi XL thanks to IPS screens, id give 2nd place to DSi. However on the 3DS there seems to be a bit of a green tint, I never noticed the green tint when playing native 3DS games. This is a shame as my 3DS top IPS screen looks less vibrant than a DSi TFT screen. The other major issue is the aspect ratio on 3DS for the top screen is slightly taller, making things look stretched out more slightly vertically, this is even apparent on pixel perfect mode and not just full screen mode. I assume this is likely due to it actually not being pixel perfect because of the 3D screen missing pixels when turned off
Finally I have comparison using TWPatch on 3DS for wide-screen. For top screen the aspect ratio doest seem bad but I heard for full 2D games it will stretch out more rather than extend the screen. Unfortunately both wide-screen options don’t look that great, the default scaling looks way too pixelated, and the GPU scaling looks way too blurry like there is a vaseline filter on top.
Reference for each image
Pic 1 – 3DS full screen Vs DSi XL
Pic 2 – 3DS pixel perfect Vs DSi
Pic 3 – 3DS wide-screen default scaling Vs DSi XL
Pic 4 – 3DS wide-screen GLU scaling Vs DSi XL