I went from Java to Scala and am back to Java 8, and couldn't be happier with my choice. We are also using the latest Spring 4 framework which plays well with Java 8.

A lot of the Spring + Java haters haven't really looked at all the improvements have happened to both Spring and Java recently, either that or they just like to bounce off what they read online without any actual experience.

It's a solid stack for a backend, and I have built the whole platform on in without a hitch.