Tube equipment reviews

After dabbling with tubed components for the first time, it becomes clear the impact of tube rolling is enormous. Therefore, it is interesting to consider reviews of such equipment: if the equipment is of a certain quality, is not the reviewer hearing the tube more than the support equipment? And if so, does that not bias the reviews?

I know my AES DJH preamp is a whole different beast depending on the tubes I've been rolling through it; it can range from respectable to outstanding.