Thanks to all testers, i think there's no testing needed anymore. All games and instruments seem to work with base IOS56. And the speed with base IOS56 seems to be the same as with base IOS57. So i recommend everybody to just use cIOS56rev20 for everything until i get reports that another base IOS is under *any* circumstances a better choice. There's are tons of different IOS bases that can be used for the cIOS now(rev20 release), so i want to figure out if the number of cIOS one could possibly need can be reduced. I think there are only 2 categories of games until now: Games that require IOS37 as base IOS(or some other, but work with IOS37 base) Games that don't require IOS37 as base Well, i would like to know which of the IOS5x can replace IOS37 completely, and will work for more games then, because it might have something that IOS5x has that other IOS don't have. Long story short: I want to know which IOS bases allow to play Monster Hunter Tri without the freeze(i hope you know where, i don't) and allow to use the usb instruments that don't work using other base IOS. So: In case of Monster Hunter Tri: install cIOS38rev20, and play until you get the freeze. And then test IOS53,55,56 and 57 up to the same point in the game. In case of the intrument games: install cIOS38rev20, and confirm that certain usb instruments won't work. And then test IOS53,55,56 and 57 if any of them gets the intrument(s) to work. Oh and please seperate the results for both, they could be different. If this works out, i'm hoping for a general recommendation like: Install a cIOS with base IOS56 for MH3 and instrument games, and one with base IOS57 for everything else. Do not test the nand emu yet, there seem to be serious issues. But of course once they are cleared, i would like to get nand emu results on the different base IOS too.