Quote: eagle, I had blind magazine rifles and went away from them because of the cleaning and unloading. I, unlike your good self, don't take the rifle out of the stock unless I really have to. The cleaning of dust, debris, mud, snow etc while hunting, the hinged floor plate works best of the two. When I get home is the only time I will remove a stock and only if I don't think it is really warranted. Mind you most of my rifles are Ceracoated and synthetic stocked. Those that are not ceracoted I rub Gilly Stephenson's Gun wax/polish into the timber and all metal parts. Yes, I am becoming lazy in my old age.
I was sold a replacement and supposedly better hinged floor plate for my Rem 700 in 35Whelen. Like you said, it undid on the first shot. Threw that away and put back the bog standard Rem floor plate, no further issues.
Just for clarity I only take my action out of the stock once home (not in the field) and only after an extended hunt in poor weather conditions or where I have been scrub bashing and have brought back half a mountainside of leaves and twigs in the rifle. I free float my barrels generously so I can tip out debris and pull an oily cloth along between the stock and barrel. Like yourself I apply a coating of rust preventative to part of the action and barrel hidden in the stock, but like to occasionally pull the action to check and clean the trigger, safety etc.
One advantage of a blind magazine in a plastic stocked rifle is that it adds to rigidity, or so they say it does, although there are other ways of 'rigidizing' a plastic fantastic.
My Mauser DG rifle has a hinged magazine but I wouldn't be too fazed if it had a blind magazine.
I must admit I had only heard about the 'nuisance' aspect of blind magazines having never had or used one until I got my cheap little Marlin in 7mm-08. I'm converted but not exclusively, just haven't come across anything adverse to them.
To the OP you can always convert a rifle to a hinged magazine but can't go the other way round without a new stock, food for thought.