Well, I have two - a small white one in my purse (4x3") and a huge orange one (10x5.5"). I usually use the smaller one - it's handier and can be used anywhere.
The huge orange dildo I usually only uses when with a guy - and yes, I can get it all. However the girth is much more important than length too me, so I usually only uses a couple of inches to warm up.
I'm 4'11".
BTW, due to a bet with an LPSG-guy, I've just borrowed a massive 10x7.5" dildo from a GF. I tried it on for size this morning and it felt really good. Haven't tried to take it all yet, but see no reason why I shouldn't be able to.