In the long run there is nothing you can do to a B18C5 that you cant to a C1....Either or, both engines are great candidates. Personally, I would go for a C1 just for the price break. Both are 1.8L DOHC VTEC engines....money can make both fast. If you need the name, just get a red valve cover and a diffrent intake manifold....no one will know the diffrence.
So ya...GSR for sure....leave the Type-R's to the all-motor auto-X guys.
cheers.