Dunno if it hogs alot of memory or not. Don't notice much difference in that window. My top 3 memory hoggers (this during raids) are still Ace2, atlasloot and one more mod that i forgot but its not fubar. (fairly sure it was my bagmod infact)
At most i use around 31mb and that is if i don't give a hoot about doing garbage collection every now and then and cleaning up Violation.
I can't say i like the config menu on Fubar 3.0 much but hopefully it will get a more familiar and simpler ui as time goes. As it is now however, it has enabled me to remove niagara/waterfall as standalone mod configuration panels so less memory to use there (not that it was alot to begin with)