My two cents, good glass probably makes the top 3 most important items to take on a mule deer hunt. You can't kill what you cant find. While a spotter is a great tool to have. I would first invest in better binos and a really good tripod (it does wonders to your glassing sessions when you have a really good tripod). Of course, you have your top 3 Zeiss, Leica, and Swaro. But, some others around the $1,000 mark are really really hard to beat (Maven, Nikon, Razors etc.) and may not be worth it for you to double the price only for an extra let's say 7 min of glassing at low light.
If you pull the trigger on higher-end binos I do not think you would be disappointed (and be surprised at how much more you see) and like all high-quality things, it is an investment especially if hunting is something you want to keep doing. This year I upgraded my tripod and my tripod head (outdoorsman pan head is worth every penny) and was surprised at how a more stable and smoother platform helps when it comes to glassing and judging animals.
If you pull the trigger on higher-end binos I do not think you would be disappointed (and be surprised at how much more you see) and like all high-quality things, it is an investment especially if hunting is something you want to keep doing. This year I upgraded my tripod and my tripod head (outdoorsman pan head is worth every penny) and was surprised at how a more stable and smoother platform helps when it comes to glassing and judging animals.