Well, it seems like all the other responses are from people who just have one engine or the other. I actually had both engines simultaneously in two different cars. So I could actually compare the two engines with one another quite well. The cars are a 1988 Civic STD HB and 1988 CRX SI (the same weight within 20 pounds). Overall, I was rather disappointed with the B18B. It just did not live up to the hype of being a 'B16A killer' that you seem to hear all the time from B18A/B18B owners. Torque really did not seem THAT much better than the B16A. And top end power fell far short. Even though the B18B had a header and the B16A didn't. Overall, the B18B was about .5 second slower in the quarter mile than the B16A. In spite of the fact that the better low end torque actually enabled me to launch better. Keep in mind that the motor I used was the better 1995 motor (using full 1995 electronics, not power-sapping 1990-1991 electronics like most EF swappers use). And although performance could have been improved with, say, a B16A transmission, this would force the engine to run at such high RPMs on the freeway that long-term freeway driving would certainly send the motor to an early grave. The bottom line: the B16A is better.
If you are even thinking about a B18B, why not consider a B20Z? This is what I replaced my disappointing B18B with. And I can tell you that it is WORLDS better. It actually DOES have alot of torque. And it has enough power for the motor to actually hold its own in the quarter mile against a B16A. The B20Z is a GREAT motor that does NOT disappoint. Unlike some motors out there.