I may not be the most qualified person to advise here but your post includes some comments that suggest our situations might be similar. Until last October, I’ve been Audaxing fairly seriously since 2007, having then been recently retired and having the time to devote to the bike.
Since then, I’d maintained an unbroken RRTY and annual SR, gained my Brevet 25,000 and notched up a PBP and two LELs. I mention this not to boast (after all, in the AUK annals, it’s a pretty commonplace palmares) but to put the following into context.
By 2013 however, age and decrepitude had caught up with me and I was suffering an unacceptable level of discomfort on the bike, primarily upper body stuff – pains in my hands, arms and head/neck. I’d done all the bike fit analysis, custom frame and position tuning stuff and still I was in pain. I don’t possess the ‘athletic gene’ and have always been a ‘full value’ rider; every Audax ride had become a race against the clock and I was no longer enjoying my Audaxing. I came to the conclusion that my Audaxing days were drawing to a close. But I didn’t want to give up without a fight and I’d always been curious about recumbents. Plus, I enjoy tinkering and a ‘bent would be a whole new area to play in!
To cut a long story short, I then went through a sustained learning curve involving several two wheelers and an ICE VTX. So how does this waffle help? Well, my conclusions are: (a) for a newcomer to recumbent riding at least, the trike is a lot slower than a two wheeler; (b) the aerodynamic advantage is available only to stronger riders who can power the machine up to the speeds where it counts – otherwise the extra weight (and drag if on three wheels) counts too much against you; (c) mastering a two wheeler is tricky if like me, you are challenged in the power-to-weight ratio area – the stall speed when climbing is rather higher than a DF – you can’t get out of the saddle to balance; (d) if your objective is proper long distance Audax, you need to pay close attention to getting the machine weight down.
Now, I have to admit that there are many riders out there to whom the above will be nonsense and who will say that they have no problem muscling a 30+ lb machine around a 600km Audax every week. But those people are the ones who have the fitness to do it. If like me, you are on the cusp of only just being able to manage to get round within the time limit on a DF, a ‘bent will not be a silver bullet. The ‘bent – whether two wheels or three - will be slower (at least at first) and you will need sufficient power-to-weight capabilities to compensate for the less efficient riding position.
I’m not saying a ‘bent isn’t a good idea for Audax – on balance, I still think they can be the perfect tool for the job – it’s just that, for me at least, it hasn’t been a straightforward solution. The usual advice for people wondering if a particular bike is right for them is to say ‘try before you buy’ but this doesn’t work for two wheeled ‘bents. You can’t just tool up and try a two wheeler because the balancing/starting/stopping learning curve takes too long and there are too many different models to be able to pick the right one at short notice.
The trike however, is different. The ICE is such a blast that even if I had to get rid of every other bike I own, I’d keep the ICE. Over longer distances especially, the ability to relax, to eat on the move, to see around corners, to stop and start halfway up a hill, to pull over anywhere and have a comfortable bed in which to doze, and the greater respect received from motorised road users, for me, all combine to make it a very attractive proposition. For Audax though, you will need a better power-to-weight ratio than on a two wheeler to maintain the necessary speed, given the extra drag and weight.
There a number of other issues I could rabbit on about, but this waffle is long enough already! I hope this helps.