Tyre inserts ?

[cryer-evo]

Hi all just wondering haw you tunne your car with tyre inserts
Ie
Soft
Medeum
Hard

What would you get from each one in the way a car handalls
I normally run schumacher med inserts all around and mimi pins our mini spikes
So would a soft compared to a hard inserts give more grip ?

Any info would be good