How accurate are the thermostat and hygrometer on the Brinsea 20 advance. Did my first hatch with no backup thermometer at 99.6 degrees F. Hatched 8 of 14 eggs. Put a secondary thermometer in the unit today and it reads 1.5 degrees lower than the primary thermostat. I doubt that the prior hatch would have gone so well with the temp that far off but worry that the primary thermostat may be losing accuracy. Will probably have to use an expensive certified thermometer to get peace of mind. Any one else have useful information on this particular bator with regards to temp? It is 5 days into 15 turkey eggs.