"Jesus flap".....never heard that before.....but......having flown an early -20(a), yes, every spring after getting used to things, I would come down final VERY high....then, full brakes and full flaps....Frikkin felt like standing on the rudder pedals but limited speed increase...impressive!
The 20C was close, but not quite as good.

Winglets help on the low speed end depending on what design....some are more high speed others are low/mid range speeds.
For most thermal spots, I would lean to a 20C since some auto hookups.
Strong thermals and ridge, I would lean to a 20B due to wingloading.