We stayed at the Catalonia Yucatan a couple of years ago. I posted a lengthy review at TripAdvisor. Search under my username "kurtsoma" to find it or send me a PM here at Debbie's.
The Catalonia is actually two smaller resorts combined. We stayed on the quieter Yucatan side. Beach was smaller and therefore a bit more crowded than we usually like. The resort is close to a lovely "town" area within walking distance which we really enjoyed exploring. Pubs, cafes, shops, etc. Not as large as Playa but still very enjoyable.
We haven't stayed at the GBP complex because we don't like huge resorts. I also understand they have a dolphin pen on the property, so out of personal principles I would never go there.
We've visited the ruins at Tulum on several occasions but always go using the collectivos (inexpensive tourist mini-van transport) and paying our own admission rather than booking a tour through the resort.