I agree on buying a lock-off as well. Trading power has so much to do with your travel habits, more than the actual resort in my opinion. I have a Shadow Ridge gold, and in the last 3 years I have traded into 1 bd Ko Olina, 2 bd Newport Coast, 2 bd Marbella, 2 bd France and 2 bd St. Thomas, and still have a 1bd on deposit. I have been able to do this because I can go anytime, therefore I just go online and pick a 6 month period to see what's available, and the best one wins. If you can do this, then the actual week does't matter.
If you have a very limited window, then you're going to have problems trading unless you own at a premium resort.
For my purpose above, Shadow Ridge, Desert Villas, Branson Platinum, Grande Vista, etc. would be what I am looking for. If your limited on when you can travel then you wouldn't be happy with these weeks and would need to go with a better trading week. I don't have any advice on these because it's not what I ever look at buying, so the only premium weeks I regularly follow are at Aruba, Hawaii and St. Thomas and I wouldn't buy them for trading because of the large maintenance fee's.
My last words of non-wisdom are about trading in general. I have noticed a large decrease in resorts available in advance at the more premium resorts using my shadow Ridge. This started immediately after the DC club. There is still availability, just not near the amount of standing inventory there used to be. Just something to think about, because I have seriously thought about selling my Shadow Ridge because of this.