Both the Sig and the Glock are wonderful weapons, in the end it is the end user's preferences and biases that will shape their decision more than anything.
If you've been shooting traditional DA w/ Decocker since the day you were born and love it, you will probably love the Sig design.
For me, I don't like DA as much as DAO striker-fired designs like the Glock, and I don't shoot the Sig as well as the Glock, and I did try. I owned a P229 .40 several years ago, and even sent it off to Robar to get it Roguard'd and NP3'd after I found out that the slide catch, mag release, and mags would rust. After I spent all that money, try as I might, I found that I could not shoot the gun as well as I could a Glock. I loved that Sig, and wish I still owned it just to marvel at it's two-tone beauty, fondle it, and feel that buttery action one more time, but I don't regret trading it for a G23 that I immediately shot better. That's just me, though.
I think it's notable that both HK and Sig are now offering DAO systems with lighter and shorter triggers (LEM module and DAK, respectively). A strong argument could be made that this is in response to the Glock design, which definitely has some advantages.
In terms of reliability, I have shot over 10k rounds through Glocks, and never had any malfunctions of any kind with anything other than cheap reloads. My Sig never malfunctioned in 2k+ rounds. The Glock is easier to maintain-- period. It just doesn't get any easier than the Glock.
There are good arguments to pick either. As for me, if I decided again to step up to a more expensive gun, it would be an HK P7M13 or perhaps a Kimber, nothing else.