Fast but you need a foot pump to fill these tyres,
This review is from: Schwalbe 26" x1.50" City Jet MTB Slick Sport Road Fast Rolling Tyre & Inner Tube Deal x 2 (Misc.)
I take my cycling fairly seriously just to keep myself fit but I've always felt something was missing on my mountain bike. Looking at some of the speeds attained by others I swear I could match them. In the end, a friend suggested I get some slicks. I did a fair bit of research and settled on these.
Firstly the tyres are fairly easy to put on but pumping them with air - well you need to get them to 80psi/6 bar. My normal pump couldn't do it (plus my arms ached!) so I used a footpump and 30 seconds later the tyres were fully pumped.
So my first journey was - unreal. You really don't have to work as hard as the rolling resistance is very low this means fast speeds are possible. You also have to adapt your style going round corners as the tyres are thin. There's no humming sound but the ride is hard but considering the performance gains its worth it.
These tyres are highly recommended as an alternative to the standard knobbly tyres that come on mountain bikes. Its also worth getting some suitable inner tubes as well.