Tommy,
You know my opinion of the work done at Merion. While I certainly applaud the tree removal, I thought the bunker work was/is anything but a "restoration" and even those who feel they came out "ok", with a heck of a lot of superintendent input and creative maintenance and bolstering over the past couple of years will admit as much. Frankly, it still doesn't compare to the original restoration work that was begun there some years ago, which was short-circuited due to a number of factors we won't get into.
You also know my opinion of the ongoing work at Pine Valley. I think the formalizing and standardized maintenance of the bunkers is hardly cause for celebration, and while some tree overgrowth has been accomplished, much more can and should be done.
Riviera is a damn shame, frankly. When I played there a few years back, only a couple of holes had been "restored", and if one were to be polite, the best that could be said is that they were completely butchered. I'm troubled to think that the 10th hole is now under construction by the same fellows, and although I hope for the best, I'm hardly optimistic.
I have never been to Winged Foot, and have only seen pictures. From those pics, I've been very encouraged by the clearing of impinging trees and the bunkers do seem to be crafted with professional care. While I don't know enough about the history and aesthetics of the course (my fault) to make a complete judgement, I'm of the feeling that whoever is doing the work on the ground there is a competent professional and someone who takes pride in their work. I'm also encouraged when someone like our friend Geoffrey gives it his blessing.
Finally, it's been over 20 years since I've been to Oakmont, and have been thrilled to hear of the tree work there that has opened vistas and avenues of play. It's one of my favorite places for golf and although I've heard mixed reports on the bunkering and teeing areas, I'm hopeful that it's maintained it's aura and architectural integrity. I do have faith in folks like Mark Studer and company, and I trust that their stewardship will continue in the right direction.
I guess overall the sense I have of Tom Fazio and crew's "restoration" efforts is simply this. With strong internal control and the selection of dligent and professional shapers the result can be successful. However, left to their own devices, I believe that Fazio's team has very little sensitivity to the nuances and aesthetics that made each of those courses so brilliantly unique in the first place, and frankly, they are best left to create their own modern courses which they do very well. For someone looking for true "restoration" however, any club considering such has to truly dictate the parameters of the work and keep a close watch on the details, lest they be left with a course that, while probably being more challenging to the modern game, also bears too much resemblance to a course built specifically for that purpose.