Have you ever chronographed them Nate? I've heard there ocasionally tough too meet the legal requirements with the available factory ammunition, though saying that I cannot imagine there's very much factory ammunition anyways so almost everyone that has them reloads.
The whole shotgun style shouldering is the reason they peaked my curiosity too, you've seen me I'm not a terribly big person one of the smaller barrelled 30-30s with iron sights seems ideal for sub 75 freehand shots, with practise obviously.
Saying that, bit sad that shotguns arent deer legal here in most circumstances they would fill that niche well.
I've had deer run within yards of me that probably could of been shot, but werent possible due too the ergonomics of the rifle and barrel length, Maybe a small chance that .243 I could shoot freehand but it depends if the scope could be set a little further back what is a lot of faff for maybe a few opportunities a year, would of been nice for the fox that ran out over the road this morning though!