I had no issues with Shapeshifter, but Tiger's speed has never enticed me. I value stability much more and in a networked PC/Mac environment Tiger has a lot of stability problems. It's implementation as a print server is a joke.
It took third party applications to work as expected in this environment and working with a Windows server required shutting off a lot of the security features on the server.
That said, just for personal use I never had issues.
I stick with Leopard though because it can be optimized and it's far more elegant in network environments (including my home network). It will never be faster than Tiger, but optimized it's quite usable and enjoyable. I'm different than a lot of other people it seems in that I am always willing to sacrifice some speed for a particular reason.
I do have Tiger Server installed on my G3 server though. The file system gets touchy with sparse bundle images created by Leopard though (such as those created from a Leopard/Snow Leopard/Mountain Lion Time Machine backup). Not a format Tiger recognizes and it doesn't really deal well with.