I have a Glock 30 with CT laser and up until a few days ago I was extremely dissapointed with all the holsters I have seen. Albeit, inside carry or outside carry and especially shoulder carry.
But I have found a company in Utah that makes the most comfortable shoulder holster I have ever worn.The design is totally different from any other SH. You can wear it ALL Day with comfort.
Check it out at Deep Conceal.com. The owner is Great and easy to work with. Also, I asked him to become a member of this site and also apply for vendor status which he did.
I am working with him to design a retainstrap on the holster That will not interfear with the on-off switch of the CT.