I have both gun bearers, the built in one on a Late Season & the Universal gun bearer. I have a sling in my pack but have not used it in years. The universal gun bearer works just as well, you just have to experiment a bit to select which location around the waist belt works better.

My mate had the Ebrestock Just one with the rear scabboard. Saw me with the gun bearer & got one as well & turfed the pack as well.

Gmoney, I'd get both the long & short straps for the universal gun bearer. The long one is for if you have a wide waist strap & the short is for when you have just webbing as a waist strap.

I'm sold on the gun bearer. Best system our there IMHO.

Also one thing people focus on is how quick you can get it into action. But sometimes people forget to look at the design of their pack shoulder straps. If you have those packs with really thick shoulder straps its hard to get a good gun mount so speed of release is useless IMHO. You have to take the pack off first, so look for packs where you can shoot with the shoulder pads in place.

Regards
JohnT