Just the facts
From an article in the Feb 97 American Rifleman by Charles E. Petty:
Walther P99
135 PDA/HS 1067 fps, 341 ft lbs, 5.37 recoil energy
124 HS 1120 fps, 345 ft lbs, 5.13 recoil energy
147 HS 925 fps, 279 ft lbs, 4.75 recoil energy
Bare gel 11.5 inches, .72 caliber
Heavy cloth 14.5/.60
From other sources for comparison:
115 Silvertip 10/.62 bare, 11.8/.58 heavy
115 +P CorBon 8.95/.52(frag) bare, 10.2/.61 heavy cloth
147 HS 13/.62 bare, 15/.57 heavy cloth
The 135 PDA/HS doesn't look so bad to me. There is a 135 +P HS for LEO BTW.