Would you upgrade your scanner or sight first?  I have 384 on both right now and I am happy with them.  However, ID of a species at distance can become challenging.  Would you prefer an upgraded 640 scanner or a the sight?

I have a 640 scanner, and a 640 scope and a couple of 384 scopes.

A 384 scanner will help spot a heat signature, and you can then look through the 640 scope to better identify what you are looking at.  

Having a 640 scanner will give you better identification at range, but you will have to get closer with a 384 optic for a clean shot.

I was hunting with my son a couple of weeks ago, and could identify hogs via the 640 scanner that he could not even see with his 384 optic.  I looked through his, and could not even identify a heat signature.  Granted, it was 1000 yards + distant.

Depending on what you are hunting and the distances involved, I would lean toward the 640 scanner as an initial upgrade.  I spend a heck of a lot more time scanning than looking through a scope.

Thank you for that! Merry Christmas

It depends on the usage. For coyote hunting for instance, 98% of the time is spent behind the scanner. I prefer the resolution there. However, this again goes towards what it will be used for and the type of terrain. If all other specs are the same, a 640 thermal will have a wider FOV and less base magnification in comparison to a 384. An example of this is a Pulsar XP50 and XQ50. Speaking of coyotes again, this lends itself to having a wider fov and less magnification (640) for the scanner vs the scope. This can be different if hunting larger groups of hogs, etc. Speak to a reputable dealer who can help you through the pros and cons of resolutions, focal length, brands, etc.

I help people everyday sort through this type of stuff. Feel free to send me a PM if you wish to dig into this further.