I wouldn't automatically dismiss a name brand bike because it has a hiten frame for your usage. The difference between the materials is that chromoly is a stronger material, but the bicycle makers take advantage of that strength by using tubes with thinner walls, therefore lighter... A hiten bike and chromoly bike can have very similar strength and longevity, but the chromoly frame will be lighter. With what you carry, I wouldn't be too concerned with the bike weighing an extra pound or two if the frame material is all that is stopping you.