Wow such prejudice against Scalextric track!
If you crimp Scalextric Sport track per the "slap my slotcar" article it is problem free. All plastic tracks expand and contract with extreme temperature variations. Avoid fixing any track down (regardless of brand) - hold it loosely in place and build any scenic items in a way that allows the track to move a few mm in all directions.
We race on Scalextric Sport track at our club every week and have no real issues with grip using standard rubber or urethane tyres. I guess we must be better drivers than those who seem to struggle with grip
Whatever track you race on the grip levels are the same for everybody on the track. If you struggle to get good grip - learn to set your car up properly and learn to drive properly - and we race magless by the way - no magnet-assisted traction for us.
I daresay that our lap times are slower than an identical Ninco track - but as everybody who is racing is doing so on the same track under the same conditions - does it really matter as long as the racing is close and fun? We can cover a 20m track with two R1 hairpins, two R2 Esses sections and a longest straight of only 4m in 8.3 seconds using a standard Scalextric F430 without magnets, with a standard 18k Mabuchi, some added weight and urethane medium hardness tyres. Pretty respectable for such undriveable slippery track and an unremarkable car.
We can't run bonkers motors as you probably can on Ninco - but it sure teaches us to strike the right balance between power, tyre compounds and weight distribution.
Every track brand has its fans and its critics. The only way to get your truth is to try driving them all and pick the one you enjoy most.