As you may have guessed, Wayne was the first to respond and will soon have another lens in the camera bag. I need to get it sent to him quickly before the mycophagists get all his morels!
You had some interesting thoughts on the Tamron 90. I'm sure that I did some testing between the two lenses years ago but time seems to have stolen that particular memory. Anyways, you made me curious so I finished off a roll of film with some comparison shots taken with the two lenses. Not a scientific test, just some close-ups of small items around the house. Looking at the results, I can't say that one lens produces sharper results than the other. They both look pretty darn good to me.
Image sharpness with the Tamron was never an issue with me. I did have problems with the Adaptall mounts wearing out after a couple of years of heavy use. That's the main reason I bought the Canon macro with its fixed mount. Ever have problems with one of the Adaptall mounts after extended use?