Other than the larger tube they are 85% the same airplane.
AFAIK the Sov + retains the old Sovs mx schedule (sort of 400hrs ish/ 6 months intervals) whereas the Lat has 800 hrs / annual intervals. That correct ?
I love the PL21 (flew it on CJs and the CHALLI 300) & hate the Honeywell Epic...
What about the Aircond ?