what's your average bg on your meter?
Just because you have tight control does not mean you will be hypo unaware... i can tell you now if a non-diabetic goes hypo's they know about it!! and they have really tight control (naturally, of course) lol.
i'd be well happy with a hba1c of 5.1 with no hypo's! actually i've be happy with 6 and no hypo's!
At the end of the day, it's not what "they" prefer your results to be, it's what YOU want and what YOU feel happy with and in control with.
I've found that GP's and Doctors are more forcefull about what they want and care less about what you want. Where-as a proper diabetes clinic who specialise in diabetes only, are far more relaxed and more accepting about what the patients wants and needs.
If you are worried about night hypo's (or nypo's as i like to call them) then wake up in the middle of the night at different times over the course of a week or so and test. At the end of the week you can put your results together and see if there are any times you are going hypo.