The round that George is referring to is a 124 grain fmj. It is the hottest 9mm ammo I've ever shot. Believe it or not, Hirtenberger states that this ammo is safe in a Glock 17, and I have shot some of this stuff safely through a 17, although I would not characterize it as a pleasant experience.
The other round mentioned is Hirtenberger's 9mm FL. This is a 100 grain truncated cone flatpoint with an exposed lead tip. This round is not as hot as the 124 grain load, and is carried by Austrian State Police in their Glocks and MP5s. The round is rated at 1475fps out of an 8" test barrel. The round is designed to penetrate autobodies and auto glass. Hirtenberger's tests show that this projectile will penetrate 18" of ballistic gelatin after passing through two .04" mild steel plates. The exposed lead tip supposedly helps the round "bite" into sufaces when striking at an oblique angle, so that it will either penetrate, or at least breakup, to prevent ricochets. Hirtenberger produces an excellent product.