I have ported S&Ws in .357, .45ACP, .41Mag and .44Mag. The removable unit on the .45 V-Comp is a waste of time but the ones on my other ported guns DO work. Accuracy is not hindered in the least bit when the revomable ports are used.
I did some chrony work last month with the 3 inch
629 V-Comp. a 6 1/2 M29 and a 7 1/2 M629 Magna classic. The recoil of the V-Comp was about the same as the other 2 guns although the weight is 6 to 10 ox. less. This was with fairly heavy loads but I assume that you WILL be using stout recepes. At milder loads of under 1,000fps and 240gr.SWCs the Comp didn't work as well. FWIW....dewey