Hello all from Battle Mountain NV,
I am new to the forum and generally excited to see this post. I have to jump in here if you don't mind. I'm kind of a geomatics nerd.
As in most things, you get what you pay for. Your average (Walmart) handheld unit will get you close to the pin and work well for general traverse navigating. If you spend a little more you can track more satellites and achieve a higher level of accuracy. I see Gjersy knows a little something about surveying or just googled Glonass. Glonass Is a Russian satellite system that compliments the trimble GNSS (as well as others). It doesnt mean anything unless you incorporate a radio link from your base station to your rover for precise accuracy. Hand helds track satellites without the use of radio, hence the (1 Meter) deviation.
Higher end Hand Helds are useful and somewhat accurate if they are tracking a good number of satellites simultaneously.
Just got back from a Nebraska black powder hunt. I will post pics soon!