plug your info into this handy calculator and it will tell you everything you need to know..
http://www.scriptasylum.com/rc_speed/_top_speed.html
The mmm is rated to 6s so it should handle it.
1. MBX-6 T8 1900KV, RX8 ON 4S
2. MBX-5T 1520, MMM ON 5S
3. MBX-5 ONROAD CONVERSION 1515, MMM ON 5S
4. MRX-3 ON ROAD CONVERSION 1512, MMM ON 6S
5. TEN T 2650 T8, MMP ON 3S