I have been using a car capsule for over 20 years on 3 different cars, a mini cooper, Caterham 7, and a miata. Still using the original car capsules so they are over 20 years old and still working fine. Only replacement was one fan/motor unit. and a new top hat looking air filter. No holes , or seam separations anywhere.
I have used in both heated and unheated garages in Central NY where temperatures have gone way below zero on many occasions. Never a problem..Lost electric power s couple of times. no problem as it just reinflates when power comes back on. Really never noticed a difference when taking the car out in the spring between heater or unheated garage. and never used in a dehumidified. Car still had no corrosion or moisture problem without a dehumidifier. I do use a dehumidifier in the summer in the garages but in the winter when it gets cold a dehumidifier doesn't work anyway. AND...no car cover, just the car. Cars come out dust free which I like.
I will say that I have put a car in on at least a couple of occasions immediately following a wash and microfiber wipe down with the rotors still wet. No corrosion as I believe the moving air dries the moisture off the rotors and all surfaces.. So my advice.....no heater and no dehumidifier needed.
I leave the windows rolled down about 2 inches and never had a mildew or damp smell..I do run a battery tender cord thru the air opening. you can set the opening to large or small by the position of the zippers as they come together and that determines the air exchange rate. Larger the opening you leave the greater the air flow.
Never mice intrusion.....maybe they don't like going into the opening because of the air escaping.
the transparent plastic top section has yellowed a bit ( not bad at all ) over the 20+ years.
If you are using a lift with cars above and below you will need to put some slats of wood beneath the floor of the top car capsule as it will balloon down without some support and infringe on the top of the lower car.
I have had a very good experience with the car capsules for the 4 and 1/2 to 5 months a year that I winter the cars. But it is a bit of work and I wouldn't plan on using it for a 1 or 2 week period.