Didn't the Air Cadets have a number of K23's at one time? - a fairly viceless piece of kit for early solos.
The best 'modern' two seat trainer is the Puchacz because of its spin and recovery characteristics. Reasonable performance, roomy front or back and aerobatic but not particularly robust or well finished and the max winch speed is only four knots above the optimum.
K13's are old hat, don't spin that well and neither comfortable or particularly accomodating in either cockpit.
7700