I would assume it would have been for WCS.
I don't think Winslow is worthy of a top 4 pick. He looks very much like a (slightly better offensively) MKG to me - and while MKG is a nice player, his play has not justified such a high pick.
In today's league (were we place so much value in athletic bigs who can defend the rim and the perimeter) I feel that WCS has more upside and more value than Winslow. Wing guys who can defend pretty good are pretty much a dime a dozen in this league - we have three of them ourselves.
On the other hand 7-foot athletic freaks with future All-Defensive Team potential are not quite so common.
I think Winslow is going to be a solid player, and I think he'll prove worth of a top 10 pick...but I don't think he'll ever be good enough that you would look back and say "yep, I'd have used #4 on him".