Although I love my iPhone 3GS, I find the front panel glass to be very fragile. That, combined with my chronic clumsiness are a bad combination. (I once had a high school football coach tell me that I had hands like feet).
The repair went flawlessly.
I would recommend spending a few extra dollars to buy the entire front panel assembly instead of just the glass. Using a hair dryer or heat gun to melt glue can seem like an eternity when removing the broken glass. If you're at all impatient here, you can ruin the repair job.