My advise is to go for both days. Chances are you will not be there all day anyway and might start late/get away early. There is the weather to consider too, how many saturdays and sundays in the year are flying days? I work through the week and instruct on sat and sun and I love it. You get the odd day off anyway due to weather and you can always say you cant come in on the odd occasion. This time of year it is hard work but I wouldnt want to do anything else with my weekends
Give it a go, if it gets too much you can always change.