While AROS has "been around" for a long time, its been in a pre-alpha state, and it has only gotten some much needed amiga-ishness implemented or fixed in the last year or so, such as changeable mouse pointer images, the scrolling and dragging screens now available in the native nvidia and intel-950 graphics drivers and a semi-working arexx implementation for applications to use. So its easy to see where people have tried it and have been disappointed by it. The windows/ios/android hosted work by sonicamiga and the m68k port work by jason and tony is currently helping to push AROS towards its initial goal of AmigaDOS 3.1 API compatibilities and an ABI-V1 alpha release faster than its ever been moving before.
