I think I'm going to be checking into the return policies of a lot of makers before I decide where to drop the money right now.
I generally never even look at return policy on holsters. I have several holsters, and I don't even know if any came with a return policy and I bought none of them locally. Chances of finding a quality holster at the local gun store is not likely. You may live in an area that has a top holster maker local, and the store may stock their stuff, but most quality holsters are bought on line. Quality holsters can be resold with very little loss, especially a holster such as a Milt Sparks that may have a 20 week waiting period, as many will pay a premium over the list price to get it with no wait.
Most of us have several holsters as it really is a trial and error effort. You can get great recommendations from the forum, and buy a quality holster, but it just may not work for you. Also, carrying a holstered gun is not as comfortable as not carrying a holstered gun, so anything you put on is going to be less comfortable than what you were doing before you started carrying.
I'll throw this out there, I'd probably choose an OWB holster, as I think they are generally more comfortable, and your gun is very small and will not extend much beyond the bottom of the belt even with an OWB holster.
Seeing Mitch Rosen covers the Max9, the OWB holster I'd start with would be the Mitch Rosen Upper Limit Express Line, which is specifically designed for small pistols like your Ruger.
https://mitchrosen.com/products/express-line/
The other thing to think of is there are several uses for holsters. A holster that may not work particularly well for concealment, may work great for a training class, or for competition, so if it doesn't work for your concealment needs, it is still available for other uses.