Tire siping for better wet and snow traction

[humblex5]

As I'm pricing out some Toyo Proxes S/T 275/40/20 + 315/35/20, the manager at the tire store suggested that I sipe my tires because I'm going to be using them year round. I've never heard of this so I did some research:

http://www.discounttire.com/dtcs/tireSiping.dos

It looks as though there are many advantages to siping including: 1. better traction in wet and snow 2. improved braking 3. quieter ride. The disadvantages seem to be debatable including uneven wear but the advanatges seem to outweigh these. I think I'm going to get this done, anyone try this before?