Yes we have. Both wife and I did last April on the Sun at St Thomas.
It was our "big" excursion for the trip. I liked it, but would rather SCUBA than BOB. The wife got sea sick on the way out to the dive site and was pretty claustrophobic inside the "helmut", but all in all, its a once in a lifetime must do kind of thing.
The captain and crew are great. They have about 24 people on the boat and you BOB in groups of eight. One diver per two BOBs. You travel about 200 yards out and 200 yards back in about 20-30 minutes. Between groups you can swim, snorkel or sun bathe on the deck.
The fish and underwater scenery are incredible in St Thomas. Our diver took my underwater camera and got some great shots of a 30" barracuda and us together with fish swimming around us. I used the MPEG function on the camera and got some great video clips while we traveled along.
There was a bait ball about 500 yards long and about 30 yards deep. I thought it was coral since the water was so dark from above. I snorkeled through it and had a blast.
I have to admit, there is a claustrophobic feeling when you first get into the helmut, you have to dive down and climb in while underwater, and it does get a little confining and hot. That's why I would prefer SCUBA to BOB and will do a Discover SCUBA next time rather than BOB.
But it is a once in a lifetime thing. I would recommend it, but with the claustrophobic caveats.
Ruby Princess - November 29, 2014 - B2B2B Caribbean
Diamond Princess - February 15, 2015 - B2B New Zealand, Then Around Australia
Caribbean Princess - June 27, 2015 - B2B2B Norway, Baltic, Norway
Crown Princess - October 17, 2015 - Tahiti
Star Princess - February 16, 2016 - B2B2B From Santiago to LA with Antartica and Machu Picchu
Grand Princess-Mexican Riviera 03/05/2014; Grand Princess-California Coastal 03/15/2014; Grand Princess-Hawaii 03/22/2014; Ruby Princess-Transatlantic 11-29-2013; Ruby Princess-Grand Med 11-17-2013; Ruby Princess-Eastern Med 11-05-2013; Ruby Princess-Eastern Med 10-24-2013; Caribbean Princess-British Isles 05-12-2013; Caribbean Princess-TransAtlantic 04-27-2013; Diamond Princess-Asia/Alaska 04-15-12; Grand Princess-Western Med 10-21-11; Golden Princess-Hawaii 04-27-11; Emerald Princess-Caribbean Combo 11-28-10; Star Princess-Antarctica 02-02-10; Golden Princess-Hawaii 9-27-09; Golden Princess-Pacific Coastal 9-19-09; Grand Princess-Caribbean Collection 3-27-09; Dawn Princess-Mexican Riviera 4-27-08; Island Princess-Panama Canal 2-06-08; Golden Princess-Mexican Riviera 9-29-07; Golden Princess-Pacific Coastal 9-23-07; Caribbean Princess-E. Caribbean 04-29-07; Star Princess-W. Caribbean 04-21-07; Dawn Princess-Mexican Riviera 12-1-06; Island Princess-Alaska 5-22-06; Island Princess-Alaska 5-15-06; Dawn Princess-Mexico 10-2005; Sun Princess-Eastern Caribbean 4-2005; Star Princess-Western Caribbean 12-2004; Island Princess-Panama Canal 1-2004; Sea Princess-Mexico 1-2002; Ocean Princess-Alaska 6-2001