Oh Boy!!! More cool kids for the Dec. 6 Sailing!!! I can't wait to meet all of you... I'm traveling alone so I'm hoping that some of you will be kind enough to buddy up with me.
This will be my 5th trip on the Nekton Pilot.
Here's my $0.02 regarding your questions:
1) Nitrox -- For me, absolutely worth it. Diving 4 -5 dives a day, I found when using air, by the last day my dives were being cut short due to limited no deco time. I know that the Rorqual had had some troubles with their Nitrox system. I believe that that has been resolved, and was never a problem on the Pilot. My last trip I consistently got 32%. Additionally, you MAY find that your consumption rate improves slightly with Nitrox.
2) Computer - I would really recommend that for safety sake you go to your local dive shop and rent a second computer for the week. While you may intend for your wife to dive the same or more conservative profile than you do, is this important safety factor really where you want to save money?
3) Spare equipment - In my experience you should not expect a wide range of rental gear on board. You should bring what you need, on the other hand you don't single handedly need to bring an entire repair shop. You'll have a friendly group of divers to share in the support. What you consider important to have duplicates of, really varies with your experience. It makes perfect sense to me that an extra dive mask would be a good thing, however, I wouldn't really think to bring one... in over 725 dives I've never broken a mask - also, I'm pretty flexible... I can wear most any mask and 'make it work' -- other people are very sensitive to mask issues and if the mask isn't exactly right then their dive is ruined. So if there is something that would just 'end' the diving for you -- bring an extra or a way to repair, etc. My save a dive kit is pretty thorough as is my first aid kit -- if there's an over the counter med (and maybe one or two others) I'm likely to have it... I'm always willing to share and my experience is that so are other divers. If a diver announces a problem of one sort or another, in my experience, several people are going to have a solution for it. Does that mean that you don't need to plan for yourself? No, of course not, but given a boat of 20 (or more) guests plus crew, there's a good chance that needs will be covered. On one Nekton trip, a diver arrived in Belize, but his luggage didn't. In fact, his luggage didn't catch up with him until Wednesday or Thursday -- but he didn't miss a dive. The crew pulled together a bunch of gear, other divers helped to round it out and offered clothes and other necessities. (I'm babbling now, but hopefully you can gather something useful from it.)
OK, it's time to go to work.... but..... ooooooh, I can't wait!!!
Liz