Tobes: It's been almost 3 years since I replaced the plastic body on my 103R with an ebony and I still remember those improvments.
I have no experience with the A90 so can't say how it would compare, but I would say that, from my perspective, the SS retip improves things in a very big way above and beyond the wood body. In two areas in particular which you mention, mid band clarity and HF refinement/extension, the SS retip probably equals or exceeds the jump in performance you experienced moving to the wood body. The SS retip brings about a huge improvement in the "hear through" quality in the mid band. It's quite amazing how much information the conical is actually missing.
It's pretty astonishing how much more detail it digs out of the grooves and it does tend to move the cartridge well into the area of being able to "satisfy those who want to count individual players of an orchestra at the rear of the stage" without really giving up that "musical rightness" IMO.
I have no experience with the A90 so can't say how it would compare, but I would say that, from my perspective, the SS retip improves things in a very big way above and beyond the wood body. In two areas in particular which you mention, mid band clarity and HF refinement/extension, the SS retip probably equals or exceeds the jump in performance you experienced moving to the wood body. The SS retip brings about a huge improvement in the "hear through" quality in the mid band. It's quite amazing how much information the conical is actually missing.
It's pretty astonishing how much more detail it digs out of the grooves and it does tend to move the cartridge well into the area of being able to "satisfy those who want to count individual players of an orchestra at the rear of the stage" without really giving up that "musical rightness" IMO.