Hi. I've got a summit.It's got the MMM in it.It WON'T work with the 27mhZ radio.I've tried everything on the castle site,ferrite ring,everything.It don't work.So I emaied traxxas,after seeing loads of adverts in loads of magazines about the power up arrangement.They DON'T do it outside of the usa . I'm in the UK,the hobby shops are either crap expensive or both! So I've got to use my summit with a 2 Ch losi 2.4Ghz radio,no locking diffs/gear change. I wish traxxas wouldn't get my hopes up like that.I'm off on holiday at the end of the month,I can't afford a 2.4Ghz at full price,and importing into the UK is a nightmare!