Thanks Guys. Points well taken.

I considered merging simply because both sites sell basically the same products, so making each unique would be somewhat difficult. My site (A) is much larger, better optimized, ranks well and had much more content. Site B has many products but little content which I think is why it doesn't rank quite as well. I am concerned about how much work it will take to get B up to speed when the same amount of work into A would probably generate more revenue. Just wondered if putting the work into A, redirecting B to A might be the best game plan. But maybe not long term.