I've finally dropped from 5 to 4 and it's such a relief. I'm doing maths, further maths, physics and chemistry (dropped tech after AS) I find that 4 is ok if they link as there are significant overlaps between some of my subjects and taking this kept more uni choices open for me. I think more is nice if you can deal with the workload and do well (like my friend who is still doing 5) but you only actually need 3.