European tyre labelling regulations require tyres to undergo testing so that comparative information can be displayed on the labels.
One of the tests is wet grip.
They are graded A - G (A being best, G being worst)
Vredestein T Trac 2 are rated B for wet grip. So almost the best.
Continental CT22 are rated F for wet grip. So almost the worst.
Among others this label helped me to go for the TT2 2.5 years ago.