You shouldn't stop using your LAMP stack. The differences between how the two behave really only come into play when you're talking about thousands upon thousands of concurrent users.
Unless you are doing it all on the same server... having less load from one part of the server means more available for other parts, which can lead to a better overall user experience. It's not quite a drop in replacement, but could be well worth considering... trying to get under 300ms page loads shouldn't be just for the big boys.
