Followed up ona rec in the tandem forum. REI has the wire bead Sec road tires for $20. Did a 60 miler on our tandem and it rolled well. Much better than the Conti Gatorskins ($36) and WAAAAY better than the Armadillos($36).

They had the tire in 700 25's and 28's. Didn't see 23's (maybe they were sold out) but IMO, I'd use these over the $60 GP4000 I just bought and of which I'm still trying to figure out the big "whoopty-doo" over these tires!