Hi, we are also DVC owners. We bought 150 points through resale at Saratoga Springs in 2005. We also just did a 50 point add on while we were at
Disneyland about 3 weeks ago. We love it! We try & get to WDW every 2nd or 3rd year (that's why we only need a lower number of points - we combine years) & have only stayed in 2 bedroom units so far. It is a very individual thing though - you really need to do the math to see if it works for "your" family.
One thing I can't recommend enough is what Queenie82 says as well. Even if buying a big number of points - keep the contracts small. These seem so much easier to sell off if the need ever arises. Even though our main one is only 150 points, if I had my time over I would put that in 50's or even a couple of 25's.
Next year we are going to try & use ours to stay at Villas at Grand California Hotel, but I don't like our chances as there are so few rooms there + we have to wait for the 7 month window. Oh well, we can only try.
Saratoga Springs seems to get a bad rap from a lot of people, but for us we love it there. It has it's down sides (too big, would love to have a proper food court as well, the pool is nothing special), but the main perk for us is being so close to Downtown Disney. So easy to walk over there & always something to do.
We have not yet stayed at any of the other DVC resorts, so have no comments on those. Hope to try them all out over time.
Good luck with your decision!