"Although, I'm pretty sceptical about this, I've been testing with Apache2 myself on a single core CPU, multi user systems, Apache2 is significantly slower even when optimized. I still wonder if this would increase my overal web and script performance or rather decrease? It made me go back to Apache v1.3; I got to note this is more than a year and a half ago. Anyone has experience on this ? "
18 months is a long time these days. I would suggest that you retry your tests as I was convinced into using Apache2 by an ex colleague of mine who said much the same as you have, but followed it with (and I paraphrase) "We now have Apache2 running significantly quicker"
From my experience (which does not compare like for like, so it is somewhat subjective) Apache2 with mod_perl2 is quicker and more robust than previous versions.