I went for a trip to the Cod Hole and Coral Sea with the Taka II last July.
Unfortunately for us the weather kicked in big time and it became too rough for us to make it to the Coral Sea. Apparently in the last 9 trips up to that point they'd only made the coral sea 4 times due to the conditions. As the sea were already choppy behind the shelter of the reef we were better off not going that far. In the words of the cruise director "You won't be able to take it, the boat won't be able to take it".....so fair enough
That said I had a thoroughly great time on board the Taka II. The crew were excellent and a great bunch of people. If you're lucky enough to have Darren in the kitchen your taste buds will be in for a treat too. They're also very good on safety and making sure that all divers are accounted for
As regards the diving that was wonderful and I'd love to go back and do it all again some day. You'll see lots of stuff you've probably never seen before. The cod feed at the Cod Hole is a heck of a lot of fun.
And although we didn't get to do the Coral Sea we did get to do Pixies Pinnacle twice which I'd happily dive many, many more times - the diversity around that site is incredible.
Water temperatures at that time of year were about 24-26C (75 - 79F) so if you feel the cold make sure you have enough protection on - I had a 3mm shortie on over the top of a 3mm full suit, kept me nice and snug 'cos I'm more used to 29/30C (84 - 86F) water
) Dive times were I think 50 mins, and when the water is chilly that's generally long enough. It's also Minke Whale season so you may be lucky enough to see one. We did see one but didn't get to swim with it as we were on our way back to Cairns after the last dive and it breached the surface near the boat.
There were about 20 divers on the boat but as we all dived in pairs you were lucky to see anyone else on a dive. Most of the time you only got to see other divers in the 5 mins or so as you made your way back to the boat.
I hear that the new boat is much better though the old one was good enough for a few days at sea. If I did the Barrier Reef again I'd be plenty happy to go out with the Taka and her crew
Cheers