I have a low mileage B18C-R without the intake manifold. Although I have a (slightly ported) del Sol VTEC manifold that I could use for it, I know that a ported Skunk2 Ultra Street from 4Piston would own that. But would I be losing too much midrange with it?

 

Yes, you would lose a ton of mid-range using a ported Ultra Street. The ported B16A I/M will make really good mid-range power and "May" lose a couple-three HP at peak compared to a stock ITR I/M. It may be worth a try.

 

One downside of the Skunk2 is the overall length.The P30's only ported at the skirt. It would be practical to stick with it but I'd like to find someone who can port it all the way or else I feel like it would be a waste of time.

 

I bet a used ITR intake manifold will cost less than paying someone to port the B16 I/M...

 

The P30 will make more power across the board than the P73 (Type R) manifold with the right work done. The money is not the issue. The issue is that I can't find anyone who can do the port work for the P30.
Another issue for me is the massive size of the Ultra Street.