Remember GTA uses MPH's Game Loader...
That's weird, Burnout for me loads only with System Menu. Different ISOs I guess. In my opinion, it really is worth converting Burnout to DAX. For me it went down to 52% of it's original size. That's half the size of the ISO, with nothing ripped. More space is always better.
Just use Direct Load after its a DAX file... NFSMW loads for me in System Menu...
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