I leveled SMN in korroloka tunnel from 25 to 66 in 3 days, 8hr work a day. Getting 2hrs back up is not an issue, just shout for a 5-10k reward upon success in whitegate and you get alot of people to try. I found it best to sync at level 11 using 4SMN+2leeches, we needed 5-7 astral flows to kill off all mobs, but seeker bats gave capped exp, and there are alot of them!
We also had 2 pullers and a giga called for help, wich we targeted to avoid hate. The only issue about this camp(at the stairs) is the jelly, so I suggest you kill it before you sync down, then get ready. good luck!