DC look cool in a retro way...
...but we have come on a good few years since Vietnam.
Despite their long track record, I do not subscribe to the 'DC is best' mindset; they are great for passive noise reduction but I believe there are lighter and more comfortable sets with ANR on the market.
I would urge you to look at this in depth - there are new models out there that will blow your previous conceptions away.
If I was to go from the start, I would be checking out the new generation of 'in ear' buds; no battery packs and moulded to you personally. Give the cans to your passengers!
If you can, try to speak with someone who works in a heavy machinery plant - they have a strict statutory requirement to prevent hearing loss which doesn't exist in aviation.
If you try to save now, you will pay later when you realise the difference. Ask your instructor if you can try his/hers. They will probably say 'no', but nothing ventured etc.