Any sane person would want a blood test.
I'm basing my information on answers given to me by three serving police officers. Convictions
are routinely secured in the UK on the basis of evidential breathalyser tests.
If you look at the sentencing guidelines
Drink Driving | Magistrates Court | Sentences you'll see that those guidelines recommend sentences based upon blood or breath analysis. I'd say these sources might be a bit more relevant to the case under discussion. A US site won't have any bearing on a UK case.