Should be expecting any major issues with my custom add-ins after upgrading to 10.3 from 10.2.2?

Going from 9 to 10 was a major change as global VBA customizations had to be converted to add-ins requiring visual studio and the SDK.

There were some differences between minor "10" version as well that required some work; newer version of VS. .NEt framework, etc.

What should I expect after upgrading to version 10.3 from my current version 10.2.2. I understand VS 2010 Express is no longer supported and I have to upgrade to 2012 when using Express? However, supported and recommended .Net framework version is still 3.5? Can someone share their experience and provide a quick rundown of what is required and what should I expect when upgrading/recompiling my add-ins.