Having experienced both, here's my take - in early stage, you want a full-cycle AE. You can title them however u want, but the most important thing in early stages is to have that person be "invested" in the company to bring the valuable feedback from the field. Once there's momentum, hire a few other full-cycle AEs while keeping an eye on splitting the responsibilities in the recent future. Once you see that the understanding of market is had, the ICP(s) are well-defined and that there's a good hunting ground, only then split it up.
SDRs will be head down prospecting and hence won't be so keen on bringing in the valuable feedback. (btw, this also relates to how you comp your sales teams, but that's not the question here)
