Never owned a DRZ, but I have a 250EXC and spent plenty of time on my buddies Tagged DRZ-E. Not even in the same ballpark. The E is way lighter than the SM, but still a pig compared to the EXC. However, the EXC has a very hard ride, and it's lack of weight can make it a very nervous machine when ridden hard.
For a daily commuter: DRZ
For an occasional commuter, weekend racer, gap-run bike: EXC