I am just getting into trikes. I bought a Catrike Dumont that has full suspension. Where I live the wind is frequently 15-20 mph with no shelter through rollers and grades. I haven't developed "bent legs" yet. I ride a DF road bike reasonably strongly for my age. My impressions:
1. I am really slow on the trike. 13-13.5 mph on the trike at the same effort on a fixed gear I would be doing 15-15.5 mph and 17-17.5 mph on a geared bike.
2. I have difficulty getting my heart rate elevated. At 13-13.5 mph my HR may be 68-72% of max. At the same effort on a DF bike it is 80% maybe a bit more. I don't know how much is due to position of heart to legs on the trike and how much is maybe my legs just can't move a bigger gear fast enough to elevate the HR compared to a traditional bike.
3. If you want to beat the wind you need a very aero position. My Dumont seat angle's lowest position is only 42 degrees. A "racing" trike like a Catrike 700 or ICE VTX is 25 degrees and a Greenspeed Aero is 20 degrees! With these low seat angles I don't think a faring will help much to increase speed. These trikes should put you into a real time trialing cheating the headwind position. But these are rigid frames and some folks don't like the laid back seat angle and getting in and out of these very low trikes. They are build for speed, not comfort.
4. Compared to a traditional road bike, a "fast trike" may be a case of a "fast turtle".
5. I am strongly considering getting a e-assist electric motor with a torque sensor and use a lower levels of assist. I know I will go a lot faster but if used properly it will allow me to get a better workout by getting on top of a bigger gear at higher cadence much like riding with a strong tailwind. I can sit in the back of my Saturday morning group averaging 17-18 mph and keep up on the trike. I think a race trike without e-assist will only get me up to 15.5-16 mph-just guessing, not sure.

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