Just an update: I've managed to find myself in rain (light) only once with this coat so far

It kept me dry, but I became alarmed by two things: 1) With the sides cinched in, the top of the hood kept sliding down and blocking my vision as I was cycling. 2) When I looked side to side, the jacket would not move with me, so I had what were essentially huge blind spots. However, today I was browsing for some alternative rain coats (I had it narrowed down to the Marmot Precip and Minimalist) when I decided to mess with the fitment of my Vaporshell some more. Turns out, it has a recessed rear cinch that alleviates all of the issues I was having on my first ride. I just took a spin around the block and all seems to be well. I'll try to make another update on my next rainy ride. I'm looking forward to it, actually!