I also dislike the open-top pro sound bags. I get the reasons for them being made that way, but I feel like for the price they should also include a complete top closure as an option for keeping out rain / dust, etc.
Why not save yourself a ton of money and get
this cheap but awesome bag which I use for my DR-70D? Dimensions of the 70D are very close to the F8. No side openings, so you probably want chopped / angled XLRs. I have since had the cables shown in the pictures below altered as such - as shown, they are chopped but with a straight-out exit.
When this bag wears out, I'm buying another one. It holds everything I need on a gig except mic cables and longer stereo bars.
Here's a thread I started when researching the bag with more discussion about it.