i'm a bit far away too... maybe... i'm at Huntingdon, which is roughly 30 miles as the crow flies.
I have heard people 30-35 miles away on a good day with my 1.8m aerial.
The response varies for me... I have it on for an hour each morning (during rush hour) and an hour each evening (during rush hour)! Sometimes I go a week without hearing a thing. Then I hear multiple people each day for a few days! Never more than 2 or 3 people though in that 1 hour/25 mile trip.
Keep putting the shout out while you're driving around - you'll get a response eventually!! Took me a fortnight to get a response though. Even when I heard people talking, I'd ask for a radio check and got no response. I was beginning to wonder if it was broken, but it was working fine the whole time - these people were just ignoring me!