I wear jackets that fit tightly across the waist and upper body, so they don't ride up at all on my torso when I'm riding. For that reason, my normal carry method of on the waist will not work.
I wanted a shoulder holster for accessibility.
I chose a Miami Classic Lite shoulder holster for a few reasons. Primarily, the harness system is exactly the same as with the higher-end models. After that- I did not need a fancy fitted leather unit, so there is considerable cost savings. The Lite model is thick suede, but has a snap and holds the gun very tight even unsnapped- it will never come out without a strong, deliberate pull.
Another thing I liked about the Lite model is that the spare mag carrier on the weak side is only a single unit, and not a double- I thought that would be too bulky for me and it has worked out to be a good decision. I've never carried two spares on my belt, so don't need two under the arm.
It may not be as easy to take off and stow away, but there are workarounds for that- on the rare occasion I have needed to take it off and stow it in public, I choose a parking spot as far away from prying eyes as possible, park and kneel down behind the bike. Then I take my jacket off, take the holster off and keep it out of sight as I pack it away. Like most things, there is usually a compromise.
I hope this helps.