Canon 100mm or Tamron 90mm Macro Lens

I am thinking of purchasing one or the two mentioned above. Would love to get others feedback to which one they prefer. I used the Tamron 60mm when I had a crop sensor and was very pleased with its performance.

I haven't tried the Tamron. However, I used to shoot with a Sigma 100mm and switched to a Canon 100mm (non-IS). The Canon focuses soooo much faster than the Sigma. Not only was the motor quicker, but it grabbed focus where the Sigma would hunt and hunt. Tiny juvenile fish were impossible to shoot with the Sigma and simple with the Canon. Based on this, I've been wary to buy a non-Canon lens.

I do have a Sigma 15mm lens and this one focuses well, so maybe the 100mm was just a fluke. However focus is not as difficult on a fisheye as on a macro in my experience.

Everyone i know who used the old Canon 100 USM macro would have testified it delivered the quality of a L version lens packed into a non L version.(and that's including me : I had two of them and still have one)

Its autofocus has a fast grip and the quality of glass is faultless, I never had a single trace of chromatic aberration.

If you can have one second hand, buy it. No brainer.