Guys/gals, nobody is changing the output power spec going from #1 to #1metal, they are just replacing one $0.25 opamp with another one which might change the sound tonality, and using a more expensive metal case which suppose to provide a better ground, shielding, emi isolation, etc. The cost difference is because you are going from a plastic case to all metal, and CNC machined dap body costs a lot more money, one of the reasons while Opus#3 is all metal but the back panel is plastic to save on cost.
You will not get a better price than $299 for opus#1 from massdrop, but keep in mind for that price you are NOT getting the otherwise included Dignis leather case. If you are planning to use #1 at home and not dragging it around too much, it's OK and you can save money. Otherwise, it's worth getting it directly from musicteck with a leather case, though you are paying additional money for a leather case. With a metal version of Opus#1, for $440 from MD you are getting leather case as well.
You gotta compare apples to apples. It's $359 Opus#1 (regular with leather case from Musicteck store directly) vs $440 Opus#1 Metal (from MassDrop, with leather case included). So, if you do want to protect your DAP and need leather case (it's a high quality genuine Dignis leather case), than we are talking about $80 difference for an all metal body and finetuning of tonality. You are not futureproofing anything or getting more power. Just getting a higher build quality model with some possible sound improvement (can't comment on it since I never compared both).
I did not know that about metal opus.
