Hi Joe,
IME, as I have 2 Performers (the 20/26" Amigo and a 700c SAKI) it depends on the recumbent.
My 20/26 (on Marathon Racers) is about 10% slower on average than my Giant DF road bike, and the SAKI (on Conti Gatorskins) is 15 to 20% faster.
I bought the SAKI (which has my Mavic road bike wheels and some of the gearset) as I wanted an audax recumbent that would keep up with the field - but I've yet to put that to the test - should be this year.
I've audaxed the 20/26 and whilst I'm not at the front, I'm by no means the slowest - but since I'm over 60 and a big lad I wouldn't expect to be.
I assume that your touring recumbent is not a 700c Highracer, but you should not let that put you off doing audaxes on it.