IMHO Depends on caliber and purpose. Glock's will be lighter, less expensive. Sigs heavier, more expensive and because of extra weight handle recoil a little better in .40 & .45 caliber. It you'll be carrying Glock will be more cumfortable.
I would get a Glock in 9m mand Sig in .40. I'm relly a 1911 guy when it comes to .45 althpough as the collection grows I'm sure to have both a Glock & Sig in those calibers too.