Funny, the constant Linux bashing on Amiga forums. Remember, without Linux there would be almost no software to run on the various Amiga clones. Almost every piece of software available for these systems are Linux ports.
I'm running Debian sid (unstable) and it's rock solid, I only reboot when I install a new kernel. And I mess a lot with my system, just for fun or to try new stuff.
About Aros being faster than Ubuntu. Well that may be, it's a very bloated distro, But I'm running a very lean setup, build everything from the ground up with a netinstaller.
I installed Icaros last summer to play around with. I have to say that installing Icaros on my laptop (a Pentium IV, the only Aros compatible hardware I have) was a very long process, I could have installed 4 linux boxes in the same time. Once installed I was very dissapointed with the speed of Aros compared to my Debian setup on the same hardware, the window managers I use (dwm, i3, pekwm, evilwm and fluxbox) run circles around Aros. I've tried it for a couple of weeks and wiped the Aros install after that.