In the end it comes down to gut feel, unless you think you like both jobs the same.
In my experience working at a large engineering company, having smart people around doesn't really help you learn much more after the first six months or so. After that, you kind of just fill a role for them and it is hard to break out of that role. You will always be "the whatever" guy or gal.
Large companies offer a lot that small companies don't, but I think (hope) that working at a small company provides more job motivation. I suspect that job motivation is the key to job satisfaction.
In my experience working at a large engineering company, having smart people around doesn't really help you learn much more after the first six months or so. After that, you kind of just fill a role for them and it is hard to break out of that role. You will always be "the whatever" guy or gal.
Large companies offer a lot that small companies don't, but I think (hope) that working at a small company provides more job motivation. I suspect that job motivation is the key to job satisfaction.