I don't use Spring a lot. But I don't see how would it have big impact on the performance. MVC's can help, but they can create a mess and extra work and frustration.
The old good way is good enough for most projects implemented by one programmer. MVC's could help when there are more than one developer.
I would use a plain servlet/jsp for most projects. If I need reusable components, I use wicket. Servlets goes with JSPs/freemarker/velocity or other template engine for presentation.
If you follow a naming pattern for your Servlets/JSP, I don't think you need Spring MVC.