OsmoBSC located next to OsmoBTS: good idea or not?

Hello Community, Quick question: if I have to set up a network where the BTS is physically distant from the MSC, such that either the A link or the Abis link has to be carried across public Internet (or inside an encrypted tunnel running over public Internet), would it be better to colocate OsmoBSC next to OsmoMSC, running Abis across the Internet- based hop, or colocate OsmoBSC next to OsmoBTS and have A running across that long hop instead? I recall hearing that the A interface carries significantly less traffic than Abis, and therefore the recommended config is to have OsmoBSC next to the BTS. However, it is only a vague recollection on my part, without certainty, hence I thought I would ask here to confirm, before I embark on a more detailed design of the proposed production network in this config. TIA, Mychaela