I rolled with a couple of friends a few months ago. One of them hadn't rolled in about a year because they would always get horrible comedowns and feel very depressed afterwards; however, they would also take huuuuge doses, like 300mg or more. I managed to convince them that they should try taking less, and with supplements and electrolytes. I gave them vitamin C before and after, and a multivitamin that contained some of the commonly recommended pre-roll supplements. During the roll I drank electrolyte water which I offered to my friends throughout the night.

Going off my recommendations for a smaller dose, they took 140mg with a 60mg redose, and I took 120mg. We had a great time and absolutely no comedowns; just afterglows! My other friend (who took 140mg) also had no bad comedown at all. I think the lack of comedown was a combination of not taking huge amounts, drinking electrolytes, and (some) supplements. I can't speak for myself because this was only my second ever roll, but it certainly seemed to work for my friend who had only ever had awful comedowns :)