I've owned them both, and they are really different beasts.
The Tweaker has a lot of tonal variety, but it's more old school tone. The Rebel gets you classic and modern rock tones, and of course, the Rebel 30 has both a clean and dirty channel, so it's a very versatile amp for a cover band player. For me, I prefer the Rebel, but I'm more of a modern rock tone guy.