Dude, heres what you do;
Buy a quarter, eat 1/8th, wait 2 hours and if you want it eat the other 1/8th. If not, eat them the next day or whenever. That is what i did on my first trip. You feel great and can function, but who knows what other people think. You may feel fully functional, but in reality be hunkered over etc. I had a 16 hour trip once, but that was on 1/2 oz. 1/8th usually lasts around 7 hours, maybe shorter maybe longer.

Another tip: dont eat anything at all the day of the trip untill you know you are trippin.

I've never had any day/morning after effects at all.