Steve Smythe again, the two entries by land doesn’t apply to dedicated visas. It’s only a limit for visa exemption entries. As OP already said he is getting a SETV at the embassy….
And again obviously that’s not a guarantee to get in, especially if the immigration officer have a bad day. In any case, it’s the “path of least resistance “
There no clear answer to that. But with a METV you can easily get close to 9 months on a single tourist visa. I did the border bounces via Laos land border.