Error notes

nisd07

as for now, I have small budget to expand my collection, however, it only good for one error due to price hike, or, multiple error but with lower grade one, I am talking about these two particular error

1. Overprint on back

or
2. Missing / inadequate inking on face

which one has more wow factor and better investment?

please note, none of these picture belong to me, I only use for reference purposes only

Thank you

Steve_in_Tampa

Personally, I would prefer to own the $20. It’s visibly a dramatic error from both the front and the back.

Serial_no_8

That's a tough question! I like both (as they're each very dramatic in their own way). I suppose it would be which denomination I don't have an error in.

goodmoney4badmoney

I would buy the $20 given the circumstances as you've stated because it will probably be the cheapest in cost of the two.

sellitstore

I'm leaning towards the $20, too. Insufficient ink isn't quite as good as missing, although on this note they appear almost the same. Both are dramatic errors.