Hemicuda: The feed ramp angles of ramped barrels should be a specific angle for the specific caliber of choice. If you had problems with your barrel, it most likely was the way the ramped barrel was fitted. I fit my ramped barrels so when the barrel is unlocked and rests on the frame, the bottom of the ramp extends slightly into the mag area of the frame. I then trim back the very bottom of the ramp. Having the feed ramp as close as possible to the magazine prevents bullets from striking the ramp at too low of an angle once the round is pushed forward from the mag. The further the ramp is from the mag, the greater the chance that a bullet will nose dive into the ramp, especially with the first few rounds out of a magazine. I am sure Virgil fixed any issues, so I am glad to hear your gun works fine.Ramped barrels typically have very steep feed ramps that don't feed well.
Do you find you retain extractor tension when moving from 9mm to .40 ?I fitted three different barrels to the STI, so I now have a very effective multi caliber gun. I do use a longer ejector when shooting 9mm, so I swap this out also when switching to the other calibers.