Find a diver you admire: buy what they have.
1. When I worked for a shop that sold ScubaPro and Aqualung, the local ScubaPro representative came by and gave us a one day offer for great keyman pricing. For the next few years I looked like a ScubaPro billboard when I dived.
2. Sometime after that, the shop began its transition to SSI and adopted the SSI philosophy that the instructor is the chief sales person and needs to wear an approved "scuba uniform." The shop identified specific gear models from the neck down (we could choose our own masks) and required all instructors to purchase (at a discount) those items and use them for instruction and personal diving in the presence of customers. We were to tell all students and any other customer that we had selected those specific items (almost all in the Aqualung family) because they were the best there was. The real reason was that they provided the best markup, because with Aqualung, the more you sell of a specific model, the lower your dealer cost for it. I quit that shop then, partially because I did not want to have to flat out lie to my students, and partially because I did not want to pruchase that equipment, not a single item of which I would use of my own free will. I therefore never had to make the transition from being a ScubaPro billboard to being an Aqualung billboard.
3. When I switched to another shop, I had to transition out of my ScubaPro stuff, but it was more complicated than that. In the meantime, I had become a tech instructor, and so in addition to the ScubaPro stuff, I had acquired the tech gear that that former shop had also sold. So it all had to go. The new shop sold Oceanic, so for the new tech program they were adding through me, they naturally had to stay in the family and go with Hollis. It took me quite a while to sell all my old stuff and fill up my inventory with Hollis, especially since Hollis was having a problem filling orders in a timely fashion.
4. I have since gone independent, and I am beginning the next transition. How long will it take me to shed my Hollis gear? Will I become a billboard for something else? I have no idea.