My wife and I were extended stay guests here for a few months back in late 2008, so my review is a little delayed, but should still apply I think.
This is actually a pretty decent RV park. I've definitely stayed at better throughout my life, but it really does have a lot going for it. The sites are roomy enough, views of the surrounding hills are nice, it was always pretty clean and quiet, there's a well-stocked store, it's very pet friendly, it has a pretty nice pool and other amenities like a clubhouse for groups, friendly staff and it's in a great location with all the major bay area spots in pretty short driving distance.
Here were my only complaints. While they did have pretty good standards for everyone keeping their site clean and neat, there were quite a few "park model" trailers here, which to me looked more like mobile homes, and in some cases were kind of dumpy looking, even if the site was neat - not to mention just a little too permanent. They definitely didn't give you the feel of staying in an RV park quite so much, and if you're just passing through and staying for a few days, you might not like this. I also didn't always feel as safe as I would like, since there seemed to be some questionable activity going on there every now and then, and you'd see police cars in there busting people. Of course I still always felt pretty safe in general, though, so not much different than a regular city neighborhood maybe - but not too great for an RV park either. There's also train tracks running right along the back of the park, so if you're staying near the back it can get pretty loud, but it didn't go by all that often, and I don't mind trains all that much myself. The dog run along the back is really weak, but at least they don't mind if you just walk your dog anywhere, as long as you pick up after it.
Basically, despite my complaints, we were pretty comfortable there and would have been plenty happy staying longer, and I do recommend it as a pretty good place to stay for that area of Morgan Hill. The only reason we left was because a spot opened up in an extra nice park on the other end of town, where we are now.