How do you apply it?

How do you remove it?

Does it stay on?

How does it react to heat (barrel)?

What to avoid?

Anyone?

I use Testors military flats on my guns when I cammie them. With a couple of coats of clear flat/dull coat, it holds up real well. You can remove it using Hoppes and some elbow grease (steel wool helps too) I've painted and completely removed it from guns without damage. You will get a better job and definition if you spray on the base(I use sand or light tan) and then brush on the rest. Unless your airbrushing, you cant get the sharper definition with the spray cans. I just recently did an AR stock set in German Flecktarn, you'd never be able to do it if you didnt use a brush. As with anything else, prep is everything, if you take your time and mask properly, you'll get a good job.

Spray cans.

Their remover or breakfree.

yes, but scratches and rubs off in high contact areas.This is a temporary camo job to match your mission area and will change with your locale or change in season, so durability is not a issue.

No problems so far.

You need to degrease the exterior of the weapon and make sure it is dry before application. Oil from the interior of the weapon will work its' way out through the pins and upper/lower receivers and darken/stain the camo job in spots but no big deal in respect to the intended use of the product.

What Tact said and it seems to stick to some surfaces better than others.  If you leave it on long term for say more than a year or two it gets more difficult to remove but is still manageable.  To make it permanent, spray it with a couple of coats of clearcoat.  I did this on a beater .22lr rifle of mine and it looks good and is holding up well.