Actually, the main reason for the "sweat shield" is not sweat, but to keep the safeties or other protrusions of the firearm from digging into your skin when sitting. Why they started being called sweat shields is beyond me....it all boils down to personal preference of comfort. I carry both styles of holster, and because of my slim build, i find the shields to be more comfortable on IWB's. Also, a majority of the manufactures now cater to the "low profiles" and actually carry very nicely without shields. Again, it is personal preference.
Warpe