I collected most of my Mercury dimes in the mid 60's by stopping in shops and asking the owners to let me check their dimes for mercuries and they would let me trade dimes. I actually found my first semi rare 26-S and 21 and many other hard to find "S" dates in loose change but that was 50+ years ago. My collection is VF+ or better except for the 16-D. I didn't want to part with $$$$ for a VF-25 16-D costing several thousand or more. I purchased my 16-D years ago because I believed I had a better chance of winning a lottery than ever finding such a rare dime. I'll bet that $350 hole filler has more than doubled in value since purchase.
Don't be scared to buy a raw coin. Just don't buy it from anyone. I bought this from an online retailer off ebay. One that backs what they sell. It is now in a slab and will go to CAC next week!
Not mentioned, so just a friendly reminder to check the 1919 for a DD Obverse. I increased the photo, but I can't tell from the photo. My personal preference would be to select this as a purchase before a 16D.