With a macro lens there really isnt going to be much of a difference in Image quality. It is all going to come down to is what kind of working distance do you want that would sway me. Would the Tamron 90mm work do I need more of the Sigma 150 range or anything else in between. Dont worry about AF either because for true macro you will be doing manual focus pretty much 99% of the time.
In the past I have owned both the Sigma 150 macro and the Sigma 105OS macro when i shot canon.
I have moved away from DSLR and now shoot Fuji Mirrorless. I havnt picked up a macro lens for this camera yet but to get me buy I use some extension tubes on my 90 f2. It doesnt give true 1:1 maco but it gets you in pretty close.
I will probably end up with the Tokina 100 macro in nikon mount and adapt it. Since it has manual aperture control and dont need AF anyway. WAY cheaper than the Fuji 80mm and wont notice any IQ difference.
So it all comes down to budget. What is it you want to spend and you really are not making any wrong choice when choosing a macro lens. More expensive doesnt mean anything in terms of IQ or what you can do with it.