Do any one know which quest give the most sp?

Well the Wizard Quests give out quite a lot specially if you do the 2-3 item quests.

Also when you have 800k you can get access to Saggitarius's quests and he can give you a lot of sP if you do his quests (never spend more then 100k on any of the quests though)

thanks for telling me Amei

Wizard quests are usually good, but as soon as you trust him and go out on a limb, he gives you junk. Personally, I like the Item hunt at the game room. Each quest, you know how much sP you'll get, so you know how much you can spend.

I like the wizard quests best. Too nervous to do Saggys

i know saggitarius give a lot of sp but the items he ask for is expensive

Saggitarius quests are DEFINITELY worth it if you're looking to gain sP, however, I wouldn't go over 15 K per item. maaaybe 20K if the other ones are cheaper. :]