One can never have too many tools.
I'm a dremel lover (yes, opening myself up for all the cheap shots) and even used mine to do the slot cutting on my first cab for t-molding but have shifted to router since that experience. I got it done but that was the only area I can think of where the dremel came in handy during construction. It was definitely a go slow process.
I use is in alot of other areas for little mods to computer/project cases, sawing off nail heads, bolt cutting, small sanding jobs, etc etc.