True! OAV is indeed a excellent treatment for broodless hives and to get an excellent knock down treatment against phoretic varroa mites. The rest of the story and the truth is that the vast majority (studies indicate in the 90% range) of varroa mites (reproductive varroa mites) reside in the capped brood of the brood nest comb. OAV does little to NOTHING to address this and inspite of OAV's excellent performance against phoretic varroa mites, the reproductive varroa mites are able to recover their numbers rapidly and endanger the survival of the hive especially if not properly treated in the Fall going into Winter. The Mighty Mite Killer DOES kill the reproductive varroa mites and totally disrupts the reproductive cycle of the varroa mite to achieve a MUCH more effective comprehensive varroa mite treatment.
Please DO enjoy "sitting on the creek bank in the shade drinking cold beer and tight lining for catfish with the rest of my 10 hours!!!" I'll gladly put in the extra hours and work to get my bees treated with thermal treatment. Next Spring when 40% - 60% of your bees are dead or in a very weak condition due to varroa mite infestation and virus's, I will be in my apiary splitting hives like a made man to stave off swarming and taking advantage of an early Spring nectar flow. Since I have begun using the Mighty Mite Killer as opposed to chemical treatments, not only have I saved a good bit of money on chemical treatments, I have doubled my numbers of hives each season. This season, I ran out of woodware to make all the full sized hives I wanted and had to used nucs until I get the new stuff wax dipped.
I have 2 ProVap 110's and they are an excellent quality mite treatment tool. I am not against OAV, on the contrary, I believe it is very wise to rotate and change up varroa mite treatment regardless of what type of mite one decides to use. That having been said, for my late Fall varroa mite treatment going into Winter, that last treatment of the season will be the Mighty Mite Killer. If for some reason I am not able to get this done, my 2nd choice is MAQS/Formic Pro. OAV being very good for what it was intended to do is NOT a good treatment to last the 5 - 6 months of late Fall/Winter/early Spring. You will likely have to retreat at least some hives during this time period and treating with OAV when the bees are in cluster is not particularly effective as compared to when the bees are out of cluster in temperatures warm enough to allow it.
Also, one should include the cost of a full face respirator equipped with organic acid rated filters ($350 - $400) (spare set of 3M P100 cartridge filters $20) (pair of welder's gloves $20) along with the cost of the ProVap 110, 10# of OA $28 plus and inverter $35.
So..........when including the FULL costs of operation of BOTH the MMK and OAV. A cheap Harbor Freight generator Tailgator 900 watt generator is about $125. The MMK cost $300. The beekeeper is ready to roll on mite treatment, $425 total cost. OAV ProVap 110 $485, 10# of OA $28, inverter $35, full face respirator $350, spare filters $20, welder's gloves $20. OAV total cost $938 call it an even $1,000 if you include the cost of a battery (not real big on prolonged running of gas equipment around my hives) The beekeeper is ready to roll.
Both of the above are excellent treatments when applied in their designed lanes of fire. The costs are NOT made up, they are what is basically required to safely conduct the treatment. Both have their advantages and disadvantages.
Even if you opt to go with a better inverter generator the cost is $167 vs the $125 for the el cheapo HB generator. https://www.homedepot.com/p/LIFAN-En...i-CA/305048506
Factor into this that the MMK wreaks havoc on small hive beetles as well. I can't say whether OAV does or not but I have read NO evidence of this.
When you compare "Apple to Apples" with respect to OAV vs. MMK thermal treatment, it may give you cause to reconsider. How much are YOU spending on chemical treatments and over time, what are their results showing? The Mighty Mite Killer is NOT the magic bullet against varroa mites in beekeeping. It IS a very effective, chemical FREE, and alternative treatment for beekeepers to employ in their IPM program. Again, I will suggest, try one.......you might find you like it and achieves the goals you are working for.
On edit: I DID leave out the cost of electrical extension cords which would be required for both types of treatments. I would guess the costs would be the same for both.