I tell everyone that toner is like stain mixed with laqure, with stain once the wood soaks it up the excess just sits there until you wipe it off, the wood will only take so much stain, toner on the other had has the stain(tint) mixed in with the lacquer so when you spray it on it stays on and hardens.
The problem I was having was the wood wasn't taking the stain, it would stain some what by you would see the walnut areas then areas that looked like maple in between. I did try oil not tinted oil but just an oil and the wood looked hideous like a cheap birch wood. It was like the wood had no color left it in, here is an example of what walnut veneer looks like
http://i25.tinypic.com/msivd4.jpg
Look a few post back to the sanded area and you notice the difference, granted that the veneer about is black walnut and the cabinets appear to be walnut. The top was even worse in color. The only true way to restore these would be to re veneer them and all honesty they aren't worth that much trouble.
I paid a 100$ for them, reason being is the horrible condition of the cabinets and I wasn't sure if the drivers would blow apart once sound hit them due to the heat. The original asking price was 200$ but once we got them down the damage was worse then suspect so price went down.