I just want to make sure before I waste $50 on a microphone.

You won't waste $50 dollars on it trust me.
They are really good microphones.

And if you download from YouTube I think the max resolution is 480p.
So your quality won't be the best.

I have one and I paid full price for it which was 110(GBP) and they are very good mics, very reliable and good quality.

Eye- wrote Yea You Should Buy It Like Terminal Was Saying You Should Get a Pop filter Im Guessing $50 Is Good (Im From Uk And its 75)

In the UK it's 45 so I have no clue what website you're using. OT: It's worth investing in. Gives more quality on your youtube channel.

To be honest, I would rather work towards getting a capture card first. Theater doesn't record in HD, and a lot of people are picky with that type of stuff where some will complain or just will click away when it's not to their liking. It is your money and decision in the end, however if you're wanting to get into YouTube, I would really think about getting an HD capture card first that way you can record what you want and then get the mic and also try to get a pop-filter with it as well.

I haven't used it but from my research I would purchase it. Probably will at some point.

Blue snowballs are good mics. It's probably your best bet.