try this one as it's in favour with the UK 12th National drivers
http://www.rcdynamics.co.uk/
I use the above and it's fine. Mine are 6v output on mine but the newer version is 7.2v I believe.
Also have this one on 4 cell in Mardave sideecar and has given no issue
http://www.actionmodelcentre.com/pro...QC%2DTQBOOSTER
beware of the cheaper ones on ebay though
as for glitching with the M'troniks item it could be anything to do with esc their using / setup / wiring etc