So much talk about disc read errors, now to see if I run into any on my machine xD I am rarely getting an error on my system menu now =S Which is odd because I haven't modified anything on it in months (haven't changed the version or installed channels in recent memory). I think it's because my broken disc drive is trying to read Twilight Princess, which I need inserted for DML to work. Oh well, it doesn't seem to have any long term affects, so I'm not going to worry about it for now.
I'm running a 4.0U Wii, DML r36, USB Loader GX r1152, from real NAND I believe (since I don't have SNEEK or etc setup)
Sandisk 4GB SDHC Class 10
Sonic Adventure 2 Battle (NTSC) - Plays full speed, did a run through 5 levels of story mode and had no issues
Super Smash Bros Melee (NTSC) - Plays full speed, did a run through Adventure Mode and had no issues
Kirby Air Ride (NTSC) - Hangs on loading a course, menus and opening video run full speed
I'll edit this post as I do more tests.