Yes, There were great. We have used them twice to Uxmal.
The first time I booked ahead and we were were going to do Chichen Itza. We messed up at the meet time was at the bus and not outside the ship. (Note the Pier is 5 miles long). They let us join the Uxmal Tour with no issues. We went in a Custom Van.
The second time we booked right there on the pier after we got off the ship. We went in an Airport Shuttle style van.
Both times they were direct trips there, no stops at the roadside tourist traps. We got there about 20 minutes before the Carnival excursion (which is operated by AutoProgresso) so we beat the crowds.
The last time we were in Progresso we did the beach tour through Carnival (just as info)