I can say for certain that tomcat is definately stable.
I cant say for sure because I dont know about your configuration but there are times when you need to restart tomcat in order to get the service to update itself if you have made changes. I dont think this should happen with jsp pages but I really cant be sure. I think there is also a way to setup tomcat so that it wont need restarts if you add another
servlet. I think this involves something called the "invoker"
I hope that helps or reasures you somewhat
Simon