Here's my take. And perhaps I'm going to piss people off by saying this. I personally like the DerbyHills home. And at some point or another I was on the wait list. My favorite is the large plan (4 i think), with the optional attic loft. It's a nice area, away from the power lines views of other homes on the side of Torrey Hills.
That said, if we could "afford" it, I would definitely would have remained on the list and at least wait until I was called to see if I could select a unit on a nice cul-de-sac. Unfortunately, my wife and I have very strict definition of "afford", which includes having not to sell our existing SFH in CV purchased in 2004, having XXXX in reserves, having XX dollars in a children's fund, having a budget to replace an 8 year-old car in 2 years. It simply wasn't an option for us. We stayed on the waitlist for awhile, in case our financial situation would drastically change, but it became a pain for us to keep track of the available lots, since we also have particular fong-shui requirements and we couldn't agree on everything So we gave up.
However, If I remember correctly, being on the list, you had the option to defer to the next phase if you were called.
That said, keep in mind also that the sales office is probably telling you things are sold out…BUT, I believe there are several more phases that they haven't started (or delayed) to control interest. If you really like this development, at least you should wait for the location you want.
Can't comment on if prices will go down. Probably so. But not everyone will care. It depends on your own situation.
My only advice to you is that you need to make sure
(1) your not in over your head if you do this
(2) you don't mind taking a hit on your current place.
However, despite what other may be saying here. I don't think a majority of these people moving in are really "stretched with arms and etc." Some, perhaps. Most…I doubt it.. I personally know some people who had existing homes were waiting for this specific new development to trade up, some were ex-qualcomm coworkers moving from other developments and putting down a lot more than 20%. The only time I recall a discount in this development was back in feb/march. There was a weeding out of the people that had contingencies that fell through. I recall several plan 2-3 were being sold with big rebates and incentives (close to 200k off). But it lasted for about 3-4 weeks.
If you do purchase, just make sure you aren't one of these that are stretched thin, otherwise I might pick your place up if you go into foreclosure