I honestly think both the SNES and N64 (at least here in Europe) have awful output quality at least with a composite cable. I think the SNES can do RGB, but that certainly isn't an option on the N64, at least not without modding. I used to have a Commodore 1084 monitor, which I thought had amazing output quality, made the PS2 look fantastic on composite and my Megadrive and Amiga totally shined on it with a SCART RGB connector.
When I tried either of Nintendo's consoles though, I was majorly disappointed. It's a shame really, especially on the N64's part, because the hardware is quite impressive for the time.
Anyway, sorry for the offtopic!
On the subject of Unreal Engine 2 games, Unreal 2 also performs like a dog, not as bad as Deus Ex 2 though. I played through the game on a Prescott 3.2GHz, 2GB RAM and a 6600GT a few years ago and the loading times were still atrocious. Not to mention occasional freezing and hanging which basically meant I had to restart the whole system. Also, there were some FPS drops here and there, even though I was only doing 1280x1024!