I totally exterminated my mites with a No Pest Strip in the room for 1 week. My room is only 20 sq ft. But the key is to entirely shut down ventilation (at least at night) to let the toxic dichlorvos vapors build up. I haven't seen a mite or a sign of them since and that was 3-4 weeks ago. Although, I was spraying with neem weekly prior to the NPS and I don't know if they were even still around.

If the NPS isn't working for you then you either aren't sealing your room and turning off your ventilation or your room is huge! If you're going to use the NPS make sure you do it right. Half-assing it is what can help these fuckers build up resistance to our arsenal of chemicals.