I have been using 4 flap MMP sabots in my Savage 50 ML. I found the Hornady sabots too soft and probably too small. They slid down the bore with very little resistance.Even with MMP sabots I found the barrel had to cool off completely between shots or the accuracy suffered. This is due to the sabots softening due to barrel heat.
I haven't tried the 2 flap sabots.
On a recent range trip at temperatures of 7 C I gave it about 5 minutes between shots. On a previous trip at about 25 C I had to wait 30 minutes between rounds and keep the sabots in the shade.
Mind you this is just about testing grouping ability. For hunting at typical muzzle loading ranges it is a non issue.
I just received some Harvester orange "crush rib" sabots which shoot very well. They were and expensive experiment due to the increases in USPS shipping rates.
Have been using 250 gr SST .452 dia. Just given some 300 grn XTP .452 dia. that I will be trying..