I'm just posting a quick vid showing the F1 to try to help out a fellow YouTuber who had some questions.
If the rails are installed right and you take your time placing the cover properly it'll be very water resistant, almost waterproof. It occasionally gets a small leak here and there that is usually remedied by my tightening the thumb screws that hold the cover on, they sometimes work loose and the cover can shift a tiny bit.
The bed has been dry after extremely bad storms and after going through the car wash, but alas, it leaked today from melting ice and a light rain. I don't blame the cover as I find that one of the thumb screws had worked loose and fell off, I also think that the cold weather effects how well the rubber seals work.
It has frozen closed one time from sudden weather shifts that took a rain like today and froze it overnight with a wind chill in the teens. When it happened I couldn't get the gate open, it fell open that night when the temp suddenly rose to well above freezing again. It had no issues through all of last winter.
Is it worth the $810 I paid? That's purely subjective and can only be answered by the person shelling out the cash- personally, I like it. I'd just like it a whole lot more at $405.