Until you determine what your max HR is the zones will not reflect your body's. It is possible to get close to your MHR while riding a trainer or riding up a longer hill. I use a figure of 174 for my MHR based on being able to hit 168 at the end of a two hour trainer workout and doing a progressive sprint until I couldn't push any harder. I have also hit the same value when sprinting at the top of a longhill, that really hurts and I almost fell off the bike.

My coach sets my training plan based on time, cadence and HR zones. He uses the Friel zones. Last year I established my zones based on Korvonens and found that I was having difficulty reaching some of the tasks assigned by the coach. There is a difference in the zone values and once we were both using the same HR zones things got a lot easier/doable for me.

In races and fast group rides I've found that it doesn't matter what HR zone I'm in because the group dictates the zone and if I want to be there I just have to ride.