I've never tried single length clubs but since learning about Dechambeau and his single length irons, I've been dying to try them.
I'm a high handicapper (used to be mid :( ) but I've always been pretty handy with the shorter irons in the bag - from 8 down to wedges. If I'm having an 'off day' with my irons, it usually comes from the longer irons, Stick a shorter one in my hand and the swing feels fine. I don't think the loft of the club has any effect on my swing, it's certainly always been the shaft length...