Best Height for B&W CDM 1NT Stand?

I just moved my Magnepan 1.6's into the living room from my office and I'm getting either the Target HR60 or HR70 stand for my B&W CDM 1NT's. I still have my original box and manual for the 1NT's but it says nothing about the correct speaker height in relation to the listeners seated position.

In my office chair (that I spend 9-10 hours a day in) my ears are 46-47" off the ground and the HR70's would place the center of the 1NT's tweeter at 42.50". Does that sound about right? I see that most people use a 24" stand for the 1NT and in my living room the seated position is much lower so I can see where that would work well but I'm wondering if the HR70 at 28" wouldn't be better for the higher seated position of my office chair.
Any input would be greatly appreciated and yes the stands have to be either the HR60 or HR70
Thanks so much!