Mine's a Pi 2 Plus or whatever the stop gap model was between the 2 and 3. It emulates everything up to the 64 really well, including 99% of the PS1 games I have on cards, which is about 45 games total. MGS runs pretty much flawless and I guess that and Gran Tourismo would be the best games to judge performance by.
I don't recommend it at all for the 64. 99% of all games lag, bug out to all or just don't work. Haven't bothered with the Saturn one since it doesn't come stock on the retro pi firmware, and there are only like two games I would even want to bother with, Astral and maybe Panzer Dragoon.
Haven't had the time to use it a long while, but I love using the PS3 generic remotes for it, easy to get them to work wireless, but on some of my cards, the wifi adapter didn't take, but got 10 ft charge cords from Monoprice for .75 each. Overall, if you want retrogaming on your main tv, and want from the ps1 and down, you can't find a cheaper, more reliable or customizable unit for the price of a Pi 2. You can save a few more bucks going with a 1 or a B, but I hear the difference between the 1 and 2 is worth it.