I have a limcat tiger top end on an SVI frame. No ports in the barrel, just the turbo comp. The gun is heavy. Full 5 inch slide and only lightened rear, but shoots very very flat. Functions flawlessly. Posted about problems of it being a bit front heavy and of the aimpoint comp sitting a bit high in another thread but got no reply. With the new 165 PF, I would not reccomend the big turbo comp, nor barrel porting, but then again a little dot jump never bothered me much. Anyone else feel the tiger is a bit front heavy? especially on a 5 inch slide? I may conrary to my own advice be convinced to drill holes in the slide/barrel, and have been thinking a lot of lightening the slide and comp lately (it is chromed though, and i dont know if thats a problem).