RE: Regret using 20ga for Whitetails?
A 12 or 20 will kill out to 100 yards with no problem. A dead deer is a dead deer. We have H&R Ultra's in 12 Deluxe (mine) and 20 Standard (boys).
His 20 is a tack driver with Remington Copper Solids. Mine gets nothing but Brenneke 3-inch Gold Magnums (1 3/8oz) and Brenneke 2 -3/4" Heavy Field Magnums.
Uncle Matt (in IL)