I'm not so sure that would be true. In Spain a duro was 5 pesetas and 5 duros was often used to say 25 pesetas. Even the phrase "I wouldn't pay a penny" is (and is still) "I wouldn't pay a duro". And yet duros aren't used to describe 5 centimos.

I think what will happen is that people in the UK will do their shopping in Euros, but there will persist the habit of working out the cost into 'real' money. What costs 3Euros will also be 2 pounds or 2quid. And this will go on for aaages.

We went metric in 1971 (I never learnt about pounds and ounces at school), and yet its only in the past couple of years that I can finally do my shopping properly without having to go through mental gymnastics if I want to find out if it's cheaper to buy the mushrooms in the 8oz pack or the loose ones at £8.40 a kg (I'd also put the imperial weighted vegetables in the scales to find out how much they really weighed).
Metric is much simpler, easier to calculate, more logical and yet it still took at least 30 years to make the transition.

There will be virtual quids alongside the real Euros for many years to come. I can't see Euros ever taking on the name, we'll need to find a new one.