we (straight Jacket armory) provide both pre fit barrels for AI/TL3/Origin/Axiom/VEctor and more. both for WTO/ARC lugs,
we find most folks are not going to change out barrels at the range, so purchasing a viper barrel vise and action wrench from big horn provides the best results in accuracy, and ease of use.
switch lugs, are great for their intended purpose. however its very rare to see a switch lug, or barrel nut accurate enough to place in bench rest... therefore as a builder that strives to offer the best in accuracy, i always recommend purchasing a vise for multiple barrels