It's my unbroken policy to only have long lovemaking sessions during months with vowels in the names.
Quickies are reserved for days that end in the letter "y."
I like both as well as the nice hard (moderate length) session followed by sleep. It also depends on what else you have going on in your schedule and if it's at night, whether you have an early morning or busy day.
I was with a guy once that liked going alllll night. Like to the point where at times I would wake up and need to pee but would debate bothering to get up because if I did, I knew when I returned to bed, he'd be hard and ready to go again. The first couple of times it was hot and exciting and I didn't mind the bleary-eyed fatigue the next day because I was running on sex-drenaline (often happens with new partners - who needs caffeine?!)... but after a while, it was just too much. I was only getting 2-3 hours of sleep and the non-stop sex nights continued by him following me into the shower - *after* the shower - trying to get out his door. It sounds all hot and intense but I don't want it like that every single time I see the person - especially during weekdays. On a weekend - it's a whole different story.
For me the ideal is to vary it up - sometimes you just want a hot quickie , other times a nice session for a few hours, and on a weekend the all-nighter can be perfect.
Its been a long time...either would be nice!
I say you can tell by the situation. If you both have nothing to do and want to fuck make it long, but if you're doing it during lunch, in a car, before work... make it a quickie.
Completely depends on timing and circumstances. I would always prefer hours of fooling around and sex but sometimes a quickie is all time allows.
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Our lives are defined by opportunities, even the ones we miss.
F. Scott Fitzgerald
Depends either are good for me.
i don't live of absolutes. i don't think there is a best between the two.
Depends from so many things, time, passion, partner, lust :P
As many have said, both are great. Although to chose between them depends on many things- mood, setting, time of day, partner etc..
I think time is a big factor here, if time is in abundance then a really long night is in order but a quickie can be very hot especially when you least expect it.
comparing apples and oranges. they both serve their purpose.
Quick and hard is my favorite, to be honest.
A long session does its job as well.
. I do enjoy a quickie most of the time with you, but I know you want it longer and meaningful ;) We both get what we want 
. I am pretty sure I am right. 
OL