Personally I don't see nothing wrong with adding a good silver cable to any headphone. The common practice (at least at Moon Audio) is to go for the Black Dragon instead for brighter headphones like Grados. As a matter of fact I've never seen a Grado with a hardwired Silver Dragon but there's plenty of them with the Black Dragon cables.
Anywho, I do think if you're asking which to pick between the Black Dragon or Silver Dragon (I've never heard the Blue Dragon) I'd say the Black Dragon is a safer bet, soundwise. Ask Drew and he will tell you exactly what you can expect from each cable vs the stock cable.
Ergonomically while the Dragon cables might be a bit lighter they are still a bit stiff especially vs other cables out there.
If you're willing to spend that much for a Dragon cable another option maybe would be to ask them to do a detachable cable mood and roll different cables which would be good if you already had some high end cables to play with.
Personally, I would just stick with stock cable and if you need a different headphone jack for your amp, I'm sure they can mod it for you to whatever jack you need (like a 4.4 balanced).
Edit:
Beautiful Audio out of New Zealand offers a cheaper option if you're interested in detachable cables. They sell an add on kit that is easy to install and apparently now they also sell cables for it too!