Sure compression does have its benefits; you can enable mppc on the 3745 for dialup clients:
http://www.cisco.com/en/US/tech/tk713/tk802/technologies_configuration_example09186a00801c13b3.shtml
http://www.cisco.com/warp/public/cc/pd/iosw/tech/compr_wp.htm
Some key points for MPPC:
Supports point-to-point connections for Microsoft clients.
Optimizes bandwidth utilization.
Operates under Multilink PPP (MLP) and Virtual Private Dial-Up Networks (VPDN). CCP runs under the bundled MLP interfaces. Compression takes place before the packets are handed off to the MLP layer in the transmitter side, and decompression occurs after the MLP layer distributes received packets to each interface in the bundled MLP group; therefore, MPPC is transparent to the MLP layer.
Restrictions
The following restrictions apply to the MPPC feature:
MPPC is only supported with PPP encapsulation.
Compression can be processor intensive because it requires a reserved block of memory to maintain the history buffer. Do not enable modem or hardware compression because it may cause performance degradation, compression failure or data expansion.
Both ends of the point-to-point link must be using the same compression method (STAC, Predictor or MPPC, for example).
Thanks, Mak