My answer may not be helpful since it isn't pneumatic specific.
The best remote I/O on the market IMO is the Murrelektronik stuff (although Turck has some pretty sweet stuff now).
They offer an IP67 remote IO block with different D-sub pinouts for different valves. I've used them with Numatics, SMC, etc. The great thing is you just use one style IO for many different pneumatic products, buy the standard 25 pin d-sub option (or whatever connector you hook to) and you are done.
If you use their remote IO offerings, it is usually a lot cheaper to use these blocks. If it is just a one-off manifold or something similar it might not be worth the money.
The reason I love Murr above all the rest is that thier IO all works on a single IP address. For smaller applications, the Turck stuff is awesome because it has self-programming options.