They're quite slick but if it's dry no issue. Run them between 40-60psi. The dots on the tread can clog a little with really wet mud. Dry gravel would be fine.
To be honest they're so cheap and no-nonsense I kind of forget they are there most of the time...
I have the £8 Continental Sport Contact's in 42mm and SKS Bluemels AND a bit of extra space on the 2017 725 model.
Not going back from the £8 tyre life. Barely had any punctures on them as well.