As above- I would pick the one with the biggest, fastest boats. I assume they all have Oxygen and communications gear.
Now, some popcorn...
(bring back 
!)
To help guide the inevitable posts, why do you feel drawn to to dive the Blue Hole?
I think most people are drawn to it simply because they are aware of it through the Belize Tourism Board and brilliant marketing. Sell the sizzle, throw in some steak.
It is spectacular... from the air at 5,000 feet. Once you've done it, many experienced divers relegate it to a "logbook dive" or "ticket punch" experience.
It's a long way away from everything, which means not only a long boat ride, but if one does need medical assistance, it's an even longer distance (usually) to that kind of recompression service.
Roatan's version is Mary's Place (70-90fsw). It is the one dive with dramatic architecture that is easily accessible by the bulk of divers who show up- West Enders and Cruise shippers. There are much more exciting dives on Roatan, but near-proximity and the fact that it
was "off limits" for preservation causes the insatiable desire.
The dive magazines call these "
must do" dives. Maybe ask them?
