Don't know about the Messi comparison but two things struck me about that video.
The first is that he's got more than enough pace, especially considering he's got the ball at his feet and he's jinking and jiving past people. Definitely not an issue.
Second is that he really, really needs better players around him. He must get so frustrated doing all the hard work only for his team mate to do an air shot.
He's probably not quick over 40 yards*, but very rapid over 5. Especially the first two. Changes direction and pace so smoothly.
And the most important thing about him is, he's quick upstairs. Look how easily he read those defenders, how many are just left standing. That's the Messi comparison. Foden is magic, but he's hectic, scarily intense in pulling very technical things off with his feet at ridiculous speed. Almost at the last minute. Grealish is doing more in his head. His awareness is also comparable to KDB.... KDB is so far ahead it's hard to keep up sometimes. We see assists like last week for Belgium and you can't do any better in terms of vision. It's the peak. But we know sometimes it looks like no-one else could have been expected to be on the same wavelength. Grealish is a more traditional playmaker. He takes touches, leaves the defenders, and by the time the next guy is there, he's seen the team mate and found him. He's hit on something, for sure. He knows what he's aiming to do tactically, has refined it... you can see it in his running style, such unfussy balance. For all the joyous flair, there is a hint of a paired back style in what he's doing.
And the last thing is, some of those crosses in the box. Very high awareness again, but some of them are almost Silva like - eye of the needle. Really fantastic stuff. For some reason I think he'll be one to bring out the best in Mahrez.
KDB, Foden, Grealish, should be incredible. So very direct, and each in their own particular way. It'll be a bit of a change. I think the emphasis might be on the technical defenders and midfielders to keep things very very tidy indeed.
*But because of this... if Sterling leaves, we will be considerably less mobile up front than in recent years. And the midfield won't have Bernie buzzing around off the ball, being so sharp, clean and tidy.
I dunno. You can't have it all. I wonder if we may infact go back for another striker, and even a central player. Like Bennacer. Fern's great but he's not that stupid neat. Bernie was. He just kept that ball so well in advanced positions. He was the new Silva, in that regard.