Let's get the obvious out of the way: an iPad Pro with a Gamevice stuck to it looks slightly ridiculous.
t's 44cm wide and looks like someone steamrolled a Game Gear. You wouldn't want to play this outside of the house and you might shut the curtains before you play it inside the house, too.
It's not unbearably uncomfortable. You'll likely rest the iPad on your lap while you play to offset some of the weight. I found my hands started to hurt from the unnatural angle but I'm broken and old so your mileage may vary.
The Gamevice consists of two chunky black controllers, strapped together with a rubber brace, that snaps around your iPad like, well, a vice.
One side plugs into the Lightning connector which means you don't need to faff around with batteries or flaky Bluetooth nonsense. Just plug and play, as they say.
The buttons and controls are the same as you'd find on any other MFi pad, as they're all made to the same Apple standards..
That means the buttons responsive, the triggers are a bit mushy, and the analogue sticks feel nice but have horrid dead zones. For shooters, this means fine aiming is tough as your gun jerks around the screen in chunky increments.
This isn't made to the same high standards as, say, an Xbox One controller. But it does the job and works great with games like GTA San Andreas, Limbo, and Space Marshals 2.
The Gamevice doesn't cover the speaker grills or headphone jack, and it has a passthrough Lightning port so you can charge your iPad (or your Apple Pencil) while the Vice is on.
When you're finished, just rip the controller off (pull hard!), fold it in half, and chuck it in a bag.
Overall, the Gamevice is a good bit of kit. Whether you want to hold up this hefty monstrosity or just prop the iPad up and use a Bluetooth controller, though, is a matter of personal preference.