Those results are pretty accurate.
I did same analysis of all above miners about a week ago when bought plenty of them in each tribe. I was more focused of how many tokens I can mine in a year based on probability and calculate ROI.
For Archon Miner, I did a conservative estimate when ARCHONM was at 100 hive each. ROI was more than 20% for only considering mining rewards. I ignored the guaranteed rewards and hive rewards paid to miners. So overall it also comes to between 2-3 years break even if those are also considered.
Haven't bought WeedM yet, but as far as CTP and Archon miners are concerned, they are doing pretty good. Also buying STEMM now is a good decision.
Thanks for the analysis.