Yeah you can use a preset because it has an inline reg on the timmy (it does work the inline reg a little harder but wont do it any harm - just need to clean & lube more frequently)- ideally you want something with an output presure around the 500-600psi range the Xtreme reg from nitroduck is good for this - good price and works really well as others have stated.
at the moment we have timmy's set up with armagedon's, x-treme regs, Angel Air and a preset and all work quite nicely with them aswell.
Also on a side note if you want to come and take a look at the different timmy models out just come and fine TEAM PHOENIX at any tourney and they will be more than happy for you to take a look