Why do you want to use a driver with such a high Qts?
I think you may be confusing Qts (driver 'Q') with Qtc (a.k.a. Qb), system 'Q'.
A Qtc of 0.7 is usually quoted as the best for a sealed alignment. However, you have to start with a driver with a Qts lower (sometimes much lower) than 0.7 in order to achieve a sealed alignment Qtc of 0.7. Qtc is always greater than Qts.
