You're only as strong as the weakest link. A 4.0 cable on a 3.x bus will give you the fastest available speeds, which would be what the 3.x bus supports. Use a 2.0 cable on a 4.0 device with a 3.0 bus and you get the speed from the slowest part of teh chain, the cable, for 480Mbps.
Some of the recent Red articles on NFS are reading as though they're sponsored content. I can get a press release from Red, a bit of editorial perspective would help to differentiate this from the release. If it is sponsored just put a label on it so it's clear.
Favourite nifty 50? Nippon Kogaku 55/1.2. Look for a single-coated version. I haven't ever found anything quite like it. Very dreamy quality without going overboard. Sharp, but not the way we think of sharp today. It's a treat. Bought it for about $200 then had the mount modified. Sometimes you need a SuperSpeed or a 50L or something like that, but when my 55/1.2 is appropriate I'm absolutely elated to mount it because something special is about to happen.
I've never pulled a couple hundred Mbps down from Google Drive's web client. Masv varies quite a bit for me. 200Mbps on a bad day and 600Mbps on a good one. That's on gigabit.
Real bonus of masv for me is the simplicity. No folders, no applications, no permissions, no folders, just fast transfers.
If Google Drive is working for you go for it. We have G-Suite, but still use masv. It's dead simple and cheap.
I like their Portals. When we have a freelance shooter I can send them a Portal link, they can upload, then I can download. The billing stays on our end and the shooter doesn't need plugins. It's a big win.
If you do any amount of photography or autofocusing you don't want to adapt a lens like this. Native lenses are simply more reliable for autofocus. Some people have luck with some adapters and others don't. Some adapters work well with some lenses but not others. If you're spending $10k or $12k on a lens like this reliable AF is worth the premium.
As an aside you know the Sony lens will work well at the higher photo burst rates the A9 can hit.
This kind of lens is pretty niche for video. It would be used it in a fairly controlled environment on some sticks, and probably with an FS7 or a Venice. This kind of lens is pretty common for journalistic photography where the reliable AF and extra burst rate is worth the price premium.