I d heard great things about GB. I've booked it once but they cancelled. I sell quite a bit of Hyatt Ziva (older but a nice beach), Dreams/Secrets Vallarta Bay and Hard Rock. I've sold Grand Velas too, it definitely is higher end than the rest.
Dreams/Secrets has a pretty rocky beach. Didn't realize quite how bad until I saw my clients destination wedding video yesterday.
Hard Rock has a great, wide, soft sand beach. I didn't love this resort but I did like the beach and location.