it's more of an issue with VoIP resources. The G700 has 32/64 VoIP resources. 32 if you use a compressed codec, such as G.729, or 64 if you use an uncompressed codec, such as G711MU. If you have (2) E1 DS1's in a single G700, in theory you could need up to 60 VoIP resources, so if you are using a compressed codec, only 32 are available, so you can see there would be a problem with that.
You can add an MM760 to 1 slot, then you are using 3 of the 4 slots in the G700 [2 MM710 DS1's, and the 1 MM760 VoIP resource module].
the answer is, it depends on the specific application, and the details.
Mitch
AVAYA Certified Expert