I can recall posts, particularly by new-to-Subaru owners, with this same concern, and wonder if this is what you're referring to. This isn't to say that what you're experiencing can't be something different, but I don't have a good sense of what your "shift hard" feels like.When coming to a stop I can feel the car shift hard into first gear, . . .
As already mentioned, roughness can be one of the symptoms that might be experienced when Type HP ATF isn't used. However, the normal 2 to 1 downshift in the 4EAT is, nevertheless, noticeable. The transmission's electronic-control programming is designed to make use of engine braking and this exaggerates the downshift effect, especially with the tachometer visibly jumping up and the physically-sensed rate of deceleration increasing a notch just as the car approaches the stopping point.
I'm not saying you can't have a problem, but if you haven't driven similar Subarus before, it might be worthwhile doing so now for comparison. Then you'd have a better idea if your symptoms are different. Perhaps your mechanic would allow you to come along when test driving cars after servicing, or if there's similar Subaru's in your area, discussions, and even demonstration rides, with their owners could provide confirmation of a problem, or hopefully, peace of mind.