As stated in Spring 3.1 official documentation
"Spring provides a couple of out-of-the-box solutions for JSP and JSTL
views."
Also you have to think about the fact that JSPX aims to produce pure XML compliant output. So if your target is HTML5 (which can be XML compliant but increase complexity see my next comments) you got some pain to achieve your goal if you are using Eclipse IDE... If your goal is to produce XHTML then go for JSPX and JDeveloper will support you...
In one of our cie projects we made a POC with both JSP and JSPX and made PROS and CONS and my personal recommandation was to use JSP because we found it much less restrictive and natural to produce HTML5 in a non XML way which is also less restrictive and more compact syntax. We prefer to pick something less restrictive and add "best practices" recommandations like "do not put java scriptlets" inside jsp files. (BTW JSPX also allows you to put scriplets with jsp:scriplet instead of <% ... %>)
