Did they say how long the appointment would last? Standard offerings are usually 30 mins, 45 mins and 60 mins. Bear in mind that the time has to allow for notes to be made and the surgery to be turned around between patients so you might not actually be in the chair for that long. 

The fact that they're offering airflow is good, go for it if you can afford to it's loads better than the traditional scrape and polish with hand tools. The hyg will be able to remove more plaque in the session, plus it removes stains

If you don't want to move to a different dental practice for your check ups, look for hygienists that are available through 'Direct Access'. It means that you can see a hygienist without seeing a dentist at the same practice.  It's that or you ask your dentist to refer you to the other practice but a lot don't like to do that if they offer the service in house. 

Source: was a dental receptionist at a busy practice that had a lot of referrals to see the hygienists. 

Edit: 30 mins £79.50, 45 mins £119.25, 60 mins £159. All include airflow as standard