Has anybody had any experience with this product.  I was looking at it for my sig p226. it is made by buffer tech...

I've never used them on anything except 1911s.  I have used those enough to know they flatten out and/or disintregrate after 300 - 1000 rounds.  When they do, they will lock the gun up more times than not.  My advice is, never put them in a gun for carry.  They are fine for the range or general plinking, but do not belong in a duty or carry gun that you want to bet your life on.  Justmy $0.02 worth.