[ou2mame]

you forget the onboard memory... that makes a huge difference. because while you can use the 4 gigs to install things to, you're limited to the way that memory behaves, which is like an sd card.. which some programs can't be installed to. i ran into problems when i had a diamond, because after i installed everything i use, i had 8mb left, and thats barely enough for cache. same software installed to my pro, i have like 120mb free. for 50 bucks more, you get an sd card, tv out (doesn't work on the diamond), keyboard, virtually unlimited amounts of program memory... its not just sd card, taste, and design, or whatever.