In reply to featuresforfeet:
It has to be entirely your decision, and try to make it as objective as possible.
ie this:
"Have been trying for literally years to get the weather, acclimatisation and partners to line up to do this; been up to the shoulder before but turned back due to snow."
and
"doesn't make a huge difference in terms of safety but psychologically having other people doing the same thing as you makes it easier."
should have no bearing.
If you're not familiar, I'd recommend googling heuristic traps.
As regards other people being around. I have met others on routes (roped and un-roped) who I wished weren't there, and have been glad not to be clipped to them (they probably thought the same about me).
Anyway, "look well to every step" and have fun.