Yes, but if you knew what you were talking about, you'd also know that 1928 is THE keydate of the Peace Dollar series.
You should be able to get 2 or 3 times more than melt on that 28. The 1921 I would keep, just because they're the coolest. I would also keep the quarters. It's all up to you.
Coinstudy.com is showing wholesale prices. This is what you can expect the average dealer to offer. Multiply by approximately 3 if you are selling to another collector or use 2012 Red Book or latest coin magazine with price list for retail value. All price lists are guides due to variations in local markets.