I think it just depends on what you want to do. I live 30 minutes from DL but we just bought into DVC (at VGC) last year and we have started to experience a whole new world of vacationing in our backyard. We actually tour the park in a whole different way. We've been AP holders for over 15 years, but as someone with a partner with disabilities we don't go for the rides or stay in the park for long periods, however since we have been staying over, we have taken advantage of the restaurants that we normally would not have visited. We take more time at the attractions. I can't imagine how people see everything in two days, they must run from one thing to the next (something that they take for granted because my DP can not even get on some of her favorite rides any more, we hope the two knee replacements will change that!)
We take things very slowly, take our time in the room, check out at 11AM and then spend another few hours touring some attractions. Until her knees are fixed, she waits and reads a book while I go on a couple rides and then we head home. Or like the last stay for the
D23 event, we spent two days in "Disney seminars" so on the third day instead of doing the scavenger hunt we went to Goofy's Kitchen buffet, before heading home.
The point I'm trying to get to is that it doesn't matter where you go for your eight days, you can find things to do. If you're a "junkie on the run" and have to be moving the whole time, there is plenty to do in So Cal if you get bored at Disney, however, as a local, I have a feeling that we could stay eight days at the resort (if we had the points) and leisurely check out all the rides we wanted, take naps, go to the spa, hang out at the pool, cook a few meals in our DVC room, have some GREAT meals out on the town and really enjoy ourselves. The only problem is that I would want to drive home and see our kitties being so close!
It all depends on how you spend your vacations as to where you go. Personally I find it hard to plan eight days at WDW because I'm afraid it's not enough, I'm working on my 2011 trip (see my sig for PTR) and I'm still trying to figure out how many days to go and exactly when. We have another 30 or so days to decide for the initial reservation, but it all comes down to how much do you want to run around, becuase at WDW you can't do it all EVER! At DLR you probably actually could if you really tried and gave yourself enough time.