I am sure all the above mentioned holsters are excellent ones especially the com-tac and premium leather ones.
Look at the Glocktalk board favorable comments on the Sidearmor line of Krydex holsters for the Glocks and 1911 et al.
The Sidearmor holster is loved by Glock, 1911 and Sig fans. It is extremely well crafted and thought out with many screw on options such at attachment method, cant angle, and other features. At this time the Sidearmor folks have just moved their shop but are designing and crafting one of their holsters to fit the P99 in .40 or 9MM. I personally use them for my Glock and 1911 and find them thinner, stronger, impervious to moisture and sucure snug fitting and as comfortable as possible for an in the waistband holster (IWB).
A group of thirty members of this board joined in a group purchase as an incentive to have Sidearmor design (blueprint)and make one of their IWB holsters for the P99. You can contact Sidearmor directly for a purchase if you wish.
Have patience at to their availability if you are interested.