DBO is the fastest as it's DBs native format. X is next as it's quick to load, but it gets converted internally into DBO format anyway.
3DS shouldn't really be used as it's no longer supported due to it's many varying file formats.
Some people however will create all their object in 3ds format when developing them, then save them to X format for DB use. (Then convert them into dbo format for speed)
I however, use truespace's native SCN for scene information and save to X format for game use.
My signature is NOT a moderator plaything! Stop changing it!
