(Floating thermometer v.s. digital)who to trust?

All iv had on the tank up untill now was a cheap floating thermometer with the suction cup to keep it still.I went out and got a little digi thermometer today and stuck it in.The digi is showing 2.5 degrees less than the floater.
Which one do I trust?

 

The digis have a tendency to be very inconsistent. So I would go with the floater.

 

Go with the glass one, as 2in10 said the digital ones can be inaccurate. Especially the Coral Life ones. I have never seen one that was right.

 

I use both, so far they have been consistant

 

floaty. very inexpensive and accurate