I bought the SmartCode deadbolt after trying it at a model home. Not only it was functional, it was so simple to replace our existing Kwikset deadbolt with just a screw driver. It was truly a direct replacement and I was able to use all the existing hardware other than the lockset and cover. Just add 4 x AA and follow the clear instructions to program the lock. The result was so satisfying that I purchased a second unit.