@Meir Assuming $110 a week (which you say is not always) you are paying $478 per month. If you average $120 a week, it goes up to $521 per month.
That along with the hassle of constantly going down there to switch cars, not having the comfort of keeping your usual setup, (presets, Bluetooth, audio options and etc.), makes it not such an amazing deal.
Though it obviously also depends on which cars you are usually receiving.