O.K. What's your perfect boiled egg?

I spotted a strange gadget/gimmick in the kitchen area of a store recently.
It purported to change colour if placed in with the egg(s) you were boiling.
I can't remember now if it was judged by the area which changed colour or the colour to which it all changed.
It struck me as, arguably, the daftest invention since the advent of sliced bread, or even the wheel.
My perfect boiled egg must have a runny yolk, but every last trace of white must be set solid, no mean feat I tell 'ee. I mean how big is the egg you want to boil?
The ones we get weigh in at 70-75gms, the size less at 60-65gm. We bought some once at a mere 35gms, I was horrified. For the benefit of them over there one of our ounces is 28.35gms.
This one was actually boiled for 7m 30s, there being a tiny bit of runny white last time at 6m 30s.
What bloody use is a warm, raw, egg to anybody? At 2 or 3 mins, this one would probably fit that category.

I notice the "crocmes" (Thereby hangs another tail.) are showing bud already, the lass who promised the worst winter for 100 years some weeks ago down town.