So do you guys think those max HR # using that 220 calculations are really very good?
I'm 58 and those # say I should have a max using 220 = 162 or using the 210-[.5] = 181
I have a real max HR of 204 and on a good hard I'll push 184 - 189 for a good while but will need to recover for a bit, but in the 170 - 178 range I'm fine for the long hall good effort.
Below 159 HR range is a good century pace for me.
I do have a PM but these are my HR #'s

OP may of had a glitch in some way but 180 for a while does not seem like its something to worry about and a max reading of 196 either, as long as his HR is able to recover to that 115 if he stops for a min or 2.
If his HR did not drop and stayed hi for a long period that would be something of concern.
But if OP is really worried about those #'s get it checked and make sure first.
I do think your max is higher than the 165-170 you think it is.