I know this is recumbent land, but I know that you will know about small wheels and dual drive hubs, and a few of you are closet folders anyway so I'm hoping you'll forgive the intrusion

So, upgrades are being considered. Greenspeed will build me a Velocity Aeroheat with a SRAM Dual Drive II in it (not cheaply, but not too bad either, and anything I do is going to cost and this will be a lot less than buying a new folder with a dual drive built in). I would fit the new wheel to the second bike to give a 52 at the front, and run a 9 speed 11/34 at the rear. (22 - 125 gear inches). The original bike is 126mm OLD, but it is a basic steel frame and I took it out to 135mm fine when I fitted the 7 speed (though I only needed 130), so I'm not expecting problems there.
Questions - are there any issues with the Dual Drive?
1. I read that some hubs don't like being on their side (leak) but being a folder that is a usual condition for me. Are there any problems with this with the Dual Drive - I haven't heard it mentioned, but wanted to check?
2. Do I need to use the SRAM derailleur if I use an SRAM shifter, or should I just get a shifter for the click box and use standard derailleur/shifters?
3. I know I could go Capreo with 34/50 on the front (25-108 gear inches) but the front doesn't really have a place for a derailleur. While I have one working, it is a triple that just manages working as a double because the angles on the seatpost are all wrong, and I do get some cross chaining issues with it, and I fear it will be hard to get a compact front chainring system shifting properly, or at least properly across the gear range. The dual drive sounds cleaner and simpler to me - Does that sound right or should I reconsider the Capreo?
4. I'm assuming that the aeroheat will support my 120 kgs OK (my standard wheels have been fine - an advantage of small size) or is it worth getting them to build with a DeepV or something else just to be sure?
Any other thoughts? I would appreciate any opinions anyone has, especially if you have experience with the Dual Drive. Cheers.