surely decent tyres would make a bigger difference than slightly wider? (seem to remember reading that some companys 195s are comparable to anothers 205s etc anyway due to were exactly they measure)
205/50/15 is a massive price difference aswell i think, im on 195/50's and they protect the rim enough for me, they look alot thinner than most people have on almeras but i kind of like them anyway, look ok imo, not overly thin.
i think if you compared back to back a 195/50 and 205/50 of the same brand in the same conditions etc you would notice very little difference, just isnt enough of a difference to be worth the extra cost imo (sure it was about £15 MORE per tyre last time i looked), especially on the road, maybe on track the tiny difference would be worthwhile
oh and avoid ventus k102 like the plague, terrible as soon as it gets wet, kind of good as they make you slow down and not even dream of going slightly quick in the wet but no good if you need to brake quickly, half decent ish in the dry, cant complain for what i paid for them though tbh