Are you sure its not a cyclone S that was upgraded?
Are all the pivot blocks and bulkheads plastic or black aluminium?
Anyway depending on the class you will probably want a one-way or spool in the front. Some people use centre one-ways but apparently it gets gritty easily and then the handling of the car becomes inconsistent, so you have to pull the centre one-way out on a regular basis and clean it. Im not sure about the text book advantages of running a centre oneway and front oneway but i think its meant to make the drivetrain more efficient when they are used together.
If you are running 540 or stock you would probably be better off with a one-way (although i prefer a spool in stock) while in faster classes like 19T or mod a spool is more ideal.
If you use either a one-way or spool then upgrade the centre-pulley to the front belt. It will strip quite easily in small crashes. It doesnt strip with a ball diff cause when you crash the ball diff gives a little in crashes reducing the stresses transmitted through the drive train back to the centre pulley.
Now the tricky thing is that you will have to upgrade the centre layshaft. The new centre layshaft seems to have both holes so that you can use pins like on the plastic parts or a flat notch needed to fix the metal parts which grub screws, so you need to work out of you have that layshaft or not. I havent tried using the holes for the plastic parts but im pretty confident that is what they are for.
Ive got a few spools and i prefer the v3 spool like on the moorespeed cyclone..