I've been with miro for many years (when it was still called realtimeboard and was by far the best and fastest whiteboard on the internet).
Boardmix is in many ways just as powerful as miro and in some ways even offers me a better user experience. I am now testing Boardmix for some time and will probably not renew my account on miro next spring. My initial experiences have been very positive. Sure, there are still a few kinks to work out, but I'm sure the Boardmix team will continue to maintain and develop their excellent product. For example, the formatting of text blocks is still too inflexible and the user guidance is sometimes counter-intuitive.
For me it's one of the best deals ever at Appsumo, I have Tier 3 of course and I'm happy with it.
I wish the Boardmix team an excellent response and many users - not only here on Appsumo
Thank you