Re: Controlled round feed vs push feed.
I own both, but will only use CRF for a dangerous game rifle.
I hunted with a PH who used a 450 Ackley on a Win Mod 70 push feed and he had experienced extraction problems on several occassions in the past and was looking for a CRF. The lack of taper on the 450 case, small extractor and a dusty chamber and high temperatures all added up to a problem. Most CRF designs will avoid that.
The one benefit of a push feed that should be mentioned is that you can drop a cartridge in the chamber, or on the mag follower and feed it in. With a CRF you generally need to get the rim of the case behind the extractor first. When hunting DG there may be times you need to drop a round in an empty gun, then the push feed will win and you'll need to get the cartridge into the mag to feed from most CRF designs. For the same reason the CRF can suffer in capacity if that bothers you. My Win CRF allows for 3 in the mag and I can push another last round in far enough to enable the extractor to grab the rim, so mine is 3+1. In a push feed you always get mag capacity plus 1, some CRF's only give you mag capacity as the mag is too full to go the plus 1.
Yes, push feeds are fine if manipulated correctly. Sometimes that's not possible and stress casues all sorts of muscle memory problems. I've double feed jammed and had failure upsidedown (also a problem with short cartridges in long actions) when testing my push feeds to see if it's potentially a problem - and it is. Obviously I fed slowly in one case, and double stroked intnetionally the next.
My longer range rifles are currently push feed and I have no preference. I don't intend to cycle them under huge pressure, or upsidedown (the bipod won't work that way :-)).