I have the vivitar series 1 105mm and I feel guilty saying it, but I have the Series 1 90mm with matching macro adaptor. They are works of art IMHO, especially the older 90mm.
From google images
I use the 105mm more because it does not need the macro adaptor. It is a fun lens as my superfly shows...
But even though you may not use AF in macro mode, there is something to be said for the AF in regular use of the Tamron 90mm. It can be a good portrait/90mm prime lens too. The Sigma 70mm is also said to be a great lens although a bit short for my bugs. In a perfect world there would have been a series 1 200mm..... but it would have weighed a ton.
Good luck on what ever you decide. Almost all the macro lenses are good. I picked up the vivitars for 175 and 185 US, so they are out there. The Tamron 90 2.5 is also a very good lens and I have seen them often on craigslist/ebait/ and here in this forum.
But I would still like a tamron 90mm AF...