I don't agree with the stainless being heavier statement. Most iron alloys used in guns have very similar strengths and densities, so weight diffferences should be negligible assuming same slide design. I've only shot blued and plastic pistols, so I don't have anything to compare it to. As far as day to day up keep stainless is better. If you aren't diligent about wiping fingerprints off a blued gun, those prints may end up as a swirl of surface rust (readily removed with a little elbow grease and a rag with Break Free). Put my 870 up for the winter time after cleaning and put it in the safe. Next spring my finger prints were still there. Now I'm pretty anal about wiping it down and placing in the safe with a ragged hand. I'm not sure what the finish is, but my browning 12 ga automatic almost has a powder coat that seems bomb proof, but I digress.
Stainless for easier upkeep.