With regards to chrome vs. stainless vs. cadmium vs. galvanized, each of these choices have their place with regards to what your ultimate goal is, as well as your budget. Chrome, although show quality, required more maintenance to keep them looking good. There are chrome plated bolts that are stainless, however most are made of steel, thus rust can and will occur over time if they are not properly maintained.
Stainless steel, although more expensive than other choices, can be polished and with minimal maintenance, can retain a nice shine. Cadmium plated bolts are steel as well, however by most accounts will resist rust but are not rust-proof. Cadmium plated fasteners are less expensive than chrome-plated or stainless, but generally speaking more expensive than zinc-coated or uncoated fasteners. Also, cadmium plated fasteners usually are identifiable by there gold-tone color.
Galvanized fasteners are both economical and suitable for this use, however they may not give the look you are after. They will, in fact, outlast most of the items they are securing, ie wood strips, wear strips and cross sills, however they are comparable to the chrome or stainless look.
In closing, the best advantage of polished stainless steel is it gives the shiny look of chrome but will not rust. Note, stainless steel will show rust discoloration when in contact with steel but is easily removed and restored to a high luster shine. The drawback to stainless is the cost. One potential drawback to cadmium coated is the color. If you are trying to keep the look consistant, the gold-tone color may be objectionable. Also note, galvanized fasteners are also coated and will rust and/or corrode over time, if exposed to road grime, salts and other chemicals. Again all types of fasteners have a place depending on your personal taste, budget and longevity.
