Twilo, Look at Audioreview.com; you can take the comments for what they are worth, but both amps have alot of reviews. It seems the fan in the 5800 is very noisy. Both amps seem to run very hot. Another consideration would be speaker load compared to ventilation. I currently run a 5500 on a 4ohm load. It gets hot but has never shut down. I do have it out on a amp stand for ventilation reasons. I have heard both 5800/5802 in different systems. They both sounded powerfull, but not being able to a/b them; I hesitate to say one clearly sounded better. The 5802 looked cooler......if that matters. Good luck and happy listening........LR
