Ripe, I worked for Biobank pre DS. It is a very worthwhile study, can take up to around 90 mins.
You will have a computer based questionnaire, usually touch screen, then will see a nurse for general health questions, ie medications you take, BP etc, next you will have biometrics done, height, weight, lung capacity, body fat, BMI and grip strength. Finally in for some blood to be taken, around 50mls(3 tablespoons) into 6 vials so looks more than it is and will be asked if you can, to give a very small urine sample.
Any participents we could get were very welcomed as the uptake over the UK has been quite poor.
I can try to answer any questions you may have. Will check back later
They are constantly opening temporary centres around the UK, all of their centres are temporary to be honest!
I am unsure about Devon but if you email them they may be able to give you more info! The idea is to get as broad and wide a spectrum of the UK population as possible. Biobank homepage
They do say that your local press will announce plans for centres in your area, but you could call the appointment line on 0800 0 276 276, they may not be able to tell you about a centre in Devon but could possibly give more information than me.
We rearranged and went on a Saturday. We don't live far from Bristol so we all went for a day out together. I went first while DH looked after the children, then we had lunch together, then he went. We had all our travelling expenses refunded very quickly.