At the start of last season many racers believed the VIST plate was already outdated and this belief was proven to be correct last February at the 2010 Olympics.
Last season's race results also indicate that you would be better off putting a floating plate on a Hangl suspension system than you would be from sticking with your VIST plate. However, at this point it makes more sense to sell your VIST plate and use one of the new plate systems.
The Apex plate has already proven itself to be very successful, so the real question is:
How do the other plates compare to the Apex plate?
Ideally, it would be great if an unbiased expert rider (someone with no connection to any equipment manufacturer/sales company) with a racing and technical/testing background were given the new plate systems (Apex, Bomber, Donek, and SGP) to test and review for this forum.
Otherwise, you can end up with reviews that were obtained in an uncontrolled/unscientific manner, or are from unqualified individuals who do not possess expert riding/racing skills and techniques, or who do not have correct technical and biomechanical knowledge of snowboarding.