Boy now that's a loaded question. Stainless steel really doesn't 'need' finishing. Usually it's simply brushed to cut the shine. It can be blued usually anyway and it is espensive..and a hard to find someone to do it. It can also be powder coated. This has the advantage of lower cost and it can be done in many colors and even camo patterns. Blued steel really needs finishing to avoid rust. Remember tha teven if we finish a carbon steel gun the interior surfaces will still need matenance. Hard chrome his a good alternative although colors may not suit you. Armorloy used to advertise the covered th entire weapon and claimed 0 surface build up. Powder coating is an option as is plain old blue(hot salt), as don by the factories. The best may be a slow rust blue. It produces the toughest and longest wearing blue possible and with just a bit of maintenance will not cause rust problems. No weapon and that includes SS models can be claimed as maintenance free, all will rust if not cared for..