I don't have an olio, but researched them. The two models are different. For quilting, I was leaning towards the yellow.
The yellow version has higher wattage and a longer time to auto shutoff.

I opted for an iron with no auto shut off, but a large steam tank. This, however, meant that I had to train myself with a shutdown procedure for my sewing area! Auto shutoff is a nice safety feature, but 8 minutes is just too darn short for me.