An A2 birdcage is your cheapest and most effective option. A coyote hunter will see no advantage from the flash suppression but the A2 works very well for protecting the crown and barrel threads. They can be had for less than $10. The A2 also lacks a vent at the bottom which will reduce, by a small amount, how much dust is kicked up when firing from the prone. The birdcage will also help push the muzzle blast more forward than a bare muzzle or a simple thread protector. They are also easy to install and remove.
Myself, I like the Battlecomp. Reduces muzzle climb and sideblast is just a little more noticeable than from an A2. Downside is it costs around $150.
Whatever you put on your muzzle, keep it light. You'll notice the weight of a heavy muzzle device
