I've made a few things in scuba, but not scuba crepe. It's not the best if you're prone to perspiration, as I was when I was younger, but I think there are plenty of people find it fine most of the time.
This one doesn't look that thick simply because you can see the shadow of the fabric turned under on the model but it also drapes as though it has some weight.
Not for the sort of weather than we're having right now, I'd suspect, but for the average summer in the UK I think you'd have plenty of days when it was very wearable.