Multiplayer MMO middleware... Need advice.

Ok so the time has come for me to start making the multiplayer(I know I should have started way earlier). So I need the right middleware.

I have my eye on UnityParkSuit but I only really want ulink... Or should I use Photon, I prefer the pay once approach of UnityPark and it seems more specialized for unity.

My purpose is to have 64 players in one scene/server. Preferably over 100, with good physics performance. My game is rather heavy on that part.

So what is my best option do you think?

Also where is the option to buy ulink separately in thier website? I cant find it even though they seem to say you can do so, or do I have to buy the full package? I would really, really like not to spend SO much on it in one go, especially since I want only ulink now.

Here is my game: http://forum.unity3d.com/threads/omega-void-wip.200629/

Thanks.