Are there any reliability issues ociated with converting a 40S&W pistol to 9mm?

Lets use the glock 23 as an example. I found these special conversion barrels made by lonewolf (and other manufacturers as well) which allow you to shoot 9mm from the glock 23 (as long as your are using 9mm mags). Are there any reliability issues ociated with using those barrels? Do those 9mm conversion kits function just as reliably as the stock 40S&W parts? Thanks in advance.