There are links to the 5 graphed units in the “Routers vs Spindles.pdf” in post 21. Post 13 has a link to a source and price info for the “Air Cooled HSD”. Post 7 has links to my recommended inverter and the Chinese 800 Watt liquid cooled KL-800L. Performance of the KL-800L should match that graphed for the KL-800A unless it can be run faster like the liquid cooled HSD version (no cooling fans).
So, except for the added power consumption, expense, hassle, and noise for the liquid cooling system, the liquid cooled versions should be the best choice. It’s up to you if the added cost of the HSD units justifies their added expense.
Of course “the proof is in the pudding”, so it would be nice if you (and others) would share you experiences like the OP did and hopefully continues to do.
2019-04-12 Addition: This sounds like an excellent ~$600 alternative to the $1600 HSD air cooled spindle.