I can tell you from experience that Marlin lever guns will freeze badly if you are in damp/soggy freezing weather for extended periods. The hammer will refuse to stay back, among other issues. This was not from rust--this was from snow and ice working their way into the action and freezing. If you have a wall tent and a wood stove and you can thaw the gun every night, this shouldn't be a problem though.
One other thing about your CAS rifles. I could run my short-stroke Uberti and Marlin 94 many times faster than even my tuned and slicked up 1895. I had worries about short stroking my 1895 because the throw was so long (and also longer than what I was used to). The throw was so long it really wasn't much faster than a bolt action. This might not be the case with your Winchester, though.
Once you shoot a bolt action enough you'll probably notice that you do a lot of the bolt manipulation under recoil anyway. So you are not actually losing that much productive shooting time. Again difference between CAS rounds and even a warm 30-06 load.
Final note about running a bolt action quickly. If a stock is even slightly too long for you and you have to reach at all for the bolt, the bolt manipulation will be several times slower. You can test this by removing your recoil pad and temporarily shortening your LOP and running the bolt that way.
