I have visited The Jockey Club and GC of Uruguay when I was working on the MacKenzie biography.
The Jockey Club is very interesting, very well preserved MacKenzie design. The land was dead flat and he built some big mounds for green and bunker settings and some big swales for drainage, and then they planted trees in between all the holes but not really in play. The effect is sort of like a giant bumper-pool table [my brother's analogy and a good one], but the surface is all common bermuda, so it's not a fast table. 6 on the Doak scale; it's not worth flying to Buenos Aires for it, but you should definitely see it if you're there.
GC del Uruguay was disappointing, though it is right in the city of Montevideo. I've seen the green sketches to which Ran referred, but unfortunately they rebuilt all of the greens about 15 years ago and took out any severe contouring in the process, now they're just slightly tilted. The land has a bit of slope to it but there isn't any part of it which I would describe as dramatic, and the bunkers are simple rounded-off shapes ... I didn't see any pictures as to whether it used to be more elaborate, but remember this was Luther Koontz carrying out the doctor's work, not Morcom or Fleming or Perry Maxwell. Only a 4 or 5.
Cantegril in Punta del Este was a very cool club laid out by Koontz ... there is a bit of MacKenzie influence there, but no documentation whether he had anything to do with the layout, it was likely Koontz on his own. 5 on my scale.
Hopefully I will have a chance to get back down there sooner rather than later ... one of my associates is in Argentina this weekend looking at a site for our client without a country!