Thanks for your responses.
Actually, I want to use a 4-way as a 2-way without restrictor plates. I know this is possible from a "logical" perspective, but I'm concerned about the feel. For comparison, I know that using the supers as a 2-way is not good enough. The feel is just too loose. I'm just wondering if a true mechanical 4-way is any better.
If not, then I would use a restrictor, preferably on a real 4-way. Does the Oscar restrictor fit the Ultimarc sticks? I thought I read somewhere that the T-stick mounting is slightly smaller than supers and therefore smaller than the Oscar mounts (right?). I haven't read anything about the J-mounting.
Worst case scenario, I can use my Oscar's on my existing super, but the panel I am putting it on is not for 8-way games. Therefore, it would be more difficult to have to remove one set of plates and add another each time I wanted to switch games. It would be simpler to just add or remove the two-way plates when I needed them and thus the preference for a dedicated 4-way. If that 4-way can be used as a 2-way without restrictors, then there is no maintenance between games at all!