I'm in the exact same boat as you. If you have some tips on which of these shoes work better with the high insteps, I'd love to hear. I have some balmorals, but they really don't work well for high insteps.
I too am looking at the Macneils and macgregors. I need to drive down to Boston and try them both on in person.
As for your original question, the macneils look more comfortable in the instep area, and that is HUGE if the decision to wear a shoe in the morning requires you to think about how much walking you'll do, and which shoe will be more comfortable. On the other hand, I think the Mcgregors look more formal with a nicer finish, but that might just be the picture. I'd have to look at the two pairs in person.
I know, this is completely unhelpful, but I'm in the fox hole with you.