Mamba Moster Max BEC and maxi servo

[gyn77]

I would use this maxi servo on Mamba Monster Max with its internal BEC.

http://www3.towerhobbies.com/cgi-bin...?&I=LXN610&P=7

Theese are the specs of the servo:

8mA idle and 800mA at zero-load operation
Speed: 0.20 sec. at 60° w/ 8.4V battery.
Output Torque: 16.0 kg-cm (224 oz-in) at 4.8V.

Can I use it without problems or do I need an external BEC?
How many Mah can handle the mamba monster max BEC?