Arun,
I think the 2500 will offer a slightly better timbre-match to your 7002's, due to using the same size (and possibly the exact same) mid-bass drivers (and tweeters, for that matter).
I doubt if the 10 in. sub built into the 3000 is audibly "slower" than the 8-in. sub used in the 2500, since in both cases the crossover frequency to the mid-bass drivers is pretty low. "Slowness" of larger drivers is mostly relevant if they are being used as mid-bass drivers in a 2-way system (at frequencies up to 2000 Hz, say), and is not usually an issue at sub-woofer frequencies.
Also, depending on how you are doing your bass management in your receiver, the differences between the built-in subs of the 2500 and 3000 may not matter much at all. If you set your center channel to "Large", then it may make a slight difference if the 3000 goes a little lower. But, if you have it set to small, even with a fairly low frequency crossover to the main sub, you may not hear any difference.
Everything considered, I'd think that the 2500 will be a good match for your system, and you might as well save the price difference between it and the 3000.