The engine bay had 40+ years of accumulated dirt, rust and grease along with some extra paint so it needed to be stripped down completely. I decided to use a soda blaster for a couple of reasons. First, it was affordable and my compressor could keep up with the 50# unit from Eastwood. Two, I had a coupon and the blaster went on sale, so it was pretty close to the same price as (basically the same unit) the Harbor Freight plus the retro-fit. Also I have a local supplier for the media and it is significantly cheaper than Eastwood+Shipping. Third, is I can use it at the house and just rinse it down the drain because it is just soda.
It has worked out great for me so far.