Bass traps - too many choices!!

Browsed the forum and read a lot regarding bass traps. But overwhelming and still not sure what to buy. Looked at the ASC site; and their tube traps are tuned to different frequencies. eBay sells foam wedges which are advertised as corner bass traps. Relatively inexpensive too. But are they effective? I've also heard about using sand-filled cardboard tubes (used for pouring concrete). Even heard that a large potted plant set in the corner can be an effective bass trap.
Can anyone simplify this? I already have Room Tunes in my corners. Speakers are on the diagonal as my listening room is kinda squarish. So I'm just looking to put a bass trap in the corner behind and between the two speakers. But I want to make sure that whatever I buy is effective.