I have not worked with either but, to the extent there is a problem it is highly probable the problem is in mating the router to a router table designed for one specific series of router, not in mounting the King to a table.
Most routers have a removeable plate on the bottom, typically some kind of plastic about 1/8"-1/4" thick, held on with screws. That plate can be removed and a attached to a universal mounting plate. That plate is designed to set into a universal router table. The tables themselves can be inexpensively made or (not so inexpensively) purchased.
When I say "universal plate" I'm not talking about one with swiss-cheese-like holes for all routers but typically one with only the center hole for the bit. They provide instructions and you drill the holes, using the existing plate as a template.
The same technique (using the plate as a drilling template) could theoretically be used with specialty tables like the Ryobi although most of them use cast aluminum for the top with ribs for structural strength that would require milling (assuming the table was strong enough after the material was removed).
Others here will likely expound on what I've said or offer other ideas. Read what they have to say; some of them may have an even simpler solution for you. Also, we have a fair number of Canadians in the forum that have probably used King routers and can speak to the advantages and disadvantages of them. Also it is likely that the King uses the same bolt pattern as some other router and hopefully someone can speak to this.
Also, I expect some of them will speak as to their experience with 3-1/2" raised panel bits in smaller routers. Also be aware that the same proviles are available in vertical bits (panel cut vertical against the fence during the cut) with very good results. I'll leave that discussion to others that have used those bits, for I have not.
I hope this helps a little bit.
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Last edited by BigJimAK; 12-08-2009 at 02:34 AM.