It's about the same. It's even less snug than stock where the volume and power buttons are.
So, coincidentally, I just received the spigen case as an early Christmas present... I have to say it feels premium and rugged compared to the stock and J&D case.. It's very snug all over and I doesn't feel larger in the hand. OP, I'd get the spigen case, you won't regret it.
Edit: https://www.amazon.com/Spigen-Rugged-Resilient-Absorption-Carbon/dp/B01LXS2BQW
Snagged a Grey one today... Missed the amazon $354 sale the other day..
Picked up the Spigen Case, AUKEY QC3 Car Charger ($11.99 lightning deal earlier) to go with it.
I have one of these Spigen cases and I love it. Bought it when I ordered the phone and I have only ever taken it off like twice.
To answer your question, I don't have any experience with it.
However, for that price I'd suggest you check out the Spigen case.