well i got my eheim 1250 and it is a little quieter than my rio1100 and has a little more water flow... but the casing is just as hot.
also the rio gave a little emi to my monitor but the eheim doesnt....
for all the people sayin rios die... well i ran that rio for 2-3 hours DRY (accident) and it has been runnin my system for over a month now without problems.
another thing you may want to consider is the size difference:
thats a quarter in the pic for reference