Vaadin Spring Add-on xpoft vs vaadin 7.4 Spring integration

Hello Vaadiners,
I currently develop/migrate a rather large software based on the good old DBase/Clipper (running in parallel) for production,
ordering, planning, accounting etc. etc. with Vaadin and Spring.

As this is a long term development, I want to stay at least a bit on track with components upgrades. My current version
is Vaadin 7.3.x with the great spring addon xpoft. I tried ones to upgrade to vaadin 7.4, but that failed, and I did not have
the time at that moment to check why.

Does anyone have experiences with moving from the addon to the now official spring-vaadin integration?