We have several 6500 and 4500 here; the 3750 is for our remote sites.
So far we've been using a 3750 stack as the core switch, and a 2600 as the VLAN router for internal networks. The only reason we're using a 2600 for L3 is because netflow is not supported on 3750.
Lately we're seeing some sites taking performance hit due to the 2600 hardware limitation, and would like to use the 3750 to route L3 traffic, but I need to make sure the 3750 can work w/ the cache engine...