Alright so i play a lot of stuff like Iron Maiden, Van Halen, and Ozzy Osbourne, as well as stuff like Metallica and other heavier metal. I went to the stor eto try out both of these amps and i must say that i was quite impressed with both of them. I really couldnt pick one over the other very easily. They both sounded great! now i wasnt able to crank either of them so i dont really know how each would sound for gigging and such. What i would like to know is what would you guys choose or prefer if you played the kind of music i did...

I havn't tried the JCM 2000 DSL, but I just purchased the JSX combo. At high volumes there is hardly any additional gain. Usually some amps will increase in distortion at high volumes, especially the clean channels. I brought a JSX half-stack into the loud lounge at guitar center(virtually soundproof room) and cranked it and with the low gain input there was still no extra unwanted/uncontrolled distortion. And I've heard a lot of people who like to cover the same kind of music you mentioned also use the JSX. My roomate fell over when he saw me bring it home and play it, it's amazing in my opinion. It's amazing for low volumes when compared to say.. the 6505+ half-stack, and it only gets better as the master volume get's cranked.

So get an opinion from someone who uses the Marshall and maybe then you can make the best decision.
alright thanks
i was leaning towards the JSX just because it was so versatile and i could dial in a very usable marshall tone fairly easily. It would be nice to hear someone whose had more experience with the DSL to talk about it a little bit :p