Which tour to snorkle.stingray city?

We are interested in a small group tour of stingray city and snorkle spots that motors not sails(husband can get seasick with slow going boats!) Looking at nativeway, captain marvin and stingray city charter. Any advice? We are experienced snorklers who would rather pay more for a smaller group experience.

I recommend Captain Marvins.

Scandinavian Sun
Emerald Seas
Island Princess
Seaward
Norway
Westward
Sensation
Facsination
Majesty of the Seas
Dawn Princess
Inspiration
Norwegian Dream
Norwegian Sun
Grandeur of the Seas (June 2002)
Carnival Paradise (Sept 2002)
Grand Princess (June 2003)
Disney Magic (Sept 2003)
Diamond Princess (June 2004)

Here we come for our honeymoon on the Diamond Princess!!
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