The SIG P226 is an absolute workhorse. It, along with the Beretta 92, was designed for the US military procurement competition. They are designed to be rugged, reliable and accurate.
SIG's have some of the best stock DA/SA triggers out there.
SIG's (particularly the P226) have excellent reliability. We can all tell our war stories, but needless to say the P226 actually won the military procurement tests, but the Beretta beat it out with a lower parts price (speculation is insider information and us wanting nukes in Italy). The P226 should have been the US military sidearms if not for cost and politics.
SIG's are extremely accurate for stock guns. They're in the top rung of out of the box guns, and may even be the best in their given catagory.
SIG's are a known system. As much as I think the HS-2000 is neat (I don't work well with Glocks, so it may be an attractive alternative), they don't have the miles into them that soldiers, cops, and citizens have on the P226 and other SIG systems.
Yes, SIG's are worth the extra money.
EDITED for typos and to say that I think SIG's are really great looking guns. Heck, I think Glocks look okay (form over function). 1911's are beautiful. You want ugly, let's talk about Ruger centerfire semiautos.