Wilcoxr,
I have hunted for several years with the 300/221 supersonic and it is a fine 100 yd deer rifle, at least for the Texas hill country deer. Plenty accurate, and with good shot placement will do the job. Shot placement is the key though.
If you want expanding subsonics, try
http://outlawstatebullets.com/2.html.
Can't say how they work because I did not have a load worked up in time. Maybe this year.
As Curtis mentioned, subs lose stability after hitting. I had noticed when shooting that after the bullet hit the plywood at 100, the dirt would fly at strange places downrange. A tumbling heavy bullet would make a big wound channel, but would not have the hydroshock of supersonics. Regarding suppressed hunting, my I have read that it is more like bow hunting. First of all, while the 300/221 supersonics easily shoot sub moa, I have trouble getting much better than 2 inch groups at 100. Add to that the rainbow trajectory, and shooting suppressed is a whole new ball game.
My daughter shot a pig with a subsonic 208 gr Hornady last Christmas, we thought she had missed, found no blood, but subsquently found the carcass about 100 yds from the feeder. A bow shooter told me sometimes pigs don't squeal when shot. We will try it again this year.