if the question is about comparing an aluminum valvebody kit to a stainless steel valvebody, then the answer is stainless steel because it is harder than aluminum, over time, the front of the aluminum bars will "mushroom" or deform because they are rather soft.
Killer link, thank you. I've searched a lot but have found little info on this mod. I only know of Toyomoto and SRT VB, is that it? Is Toyomoto still in business. Thought I saw in another post that they are out of business, plus I called there number on their website and got no answer.
What are the differences in brand and average price???