According to Gary Farber, Times Select does nothing to impede access to columnists.
I haven’t tried it, as I am just using this opportunity to wean myself off Krugman, Herbert, and Dowd. I think my blood pressure has already dropped.
*** Update ***
Speaking of Times Select, an enterprising experiment over the next few months would be for someone with some inititative to spend some time examining the number of links to the NY Times op-ed pages and the NY Times in general prior to the switch-over, and other top newspapers (WaPo, WSJ, LA Times, etc.) and see if not only do the op-ed links drop for the NY Times, but other links as well.