That is excellent advice. We own EY at WKORV and EOY at WPORV. We haven't been to WPORV yet but we have been to Princeville before and the two areas are so different.
Factoring out the large differences in the properties and the Island, from a purely SVN standpoint, if we could only own at one place and it was in the budget, I would buy resale OF at the original WKORV as I think those are the some of the best units on any of the Islands, with spectacular views, extra space, etc... They are also holding their value reasonably well as there is less inventory when compared to the OV units (especially at WKORV - less so at WKORV-N). If you decide not to go one year, they are reasonably easy to rent as well for a decent premium over the OV units. You do have to accept that you paid a stiff premium both in purchase price and in maintenance fees for OF so trading within SVN is generally going to be a bad idea. With WPORV, being a voluntary resort, you are going to either buy resale (with no SVN access) or pay the developer premium and go in knowing you are going to lose a higher percentage of resale value as it is a voluntary resort. One of the (many) reasons we bought EOY there was to shield us from some of that depreciation.
To me it boils down to what matters most to you. Once you determine which Island/Property you prefer, you need to figure out how critical having access to the ownership reservation window (8-12 months out) and the view category (for WKORV) is going to be for you. There are a lot of different strategies to access Hawaii via SVN. If you determine that you are flexible on schedule and view isn't important, you could likely buy at Kierland for around $20k on the resale market (with much lower MFs) and trade into both WKORV and WPORV reasonably well.
We went through a similar process before determining to buy where we wanted to go most (every) year which was WKORV on the resale market. I hope this help...