I am very satisfied with this wallet, and it is in no way too big.
It's about 9.5cm by 11.5 cm when folded in your pocket. In my experience, it seems no bigger than any other wallet I've owned, and it fits in my pocket just fine. I can see that it might be a struggle to fit if I was wearing skin-tight leather...but I wouldn't be.
More importantly, the inside design is fantastic.
I think every inside design is a little bit different, which is why the website doesn't show the inside. But I know mine features comic book covers from Spiderman, X-Men, Hulk, and Iron Man, so should satisfy all Marvel fans. Even the insides of the card pockets have black and white Marvel characters across them.
Overall, the wallet's quality is very nice, with impressive looking black leatherish exterior, and a nice metal silver 'MARVEL' badge.
Admittedly, it lacks a space for coins, but so do most Men's adult wallets. And this is definitely a men's adult wallet...just with an extra geek feature on the inside.