First comment I’ve made here (I think), but have used excel from the start. While recently helping debug a connection, I added a test workbook in Sheets. I’ve used excel for decades, and sheets only more recently. I like both for general use. All to say one thing: the add-in for Excel is way more responsive (quick) than the sheets version, at least for me.
I use office 365 for other reasons, so cost isn’t a factor… but would be if I didn’t. I see parity between the two for core functions, so don’t foresee an issue with starting w one and switching to the other later.