Notes Found In Circulation - Spend Or Keep?

I have no problem with coin roll searching - the high turnover makes searching minimally impacting on my budget. But currency is just too valuable!

I made a list of Federal Reserve Notes that I've found by asking for "obsolete currency" at banks. I didn't include $2 red seals, or $1/5 blue seals. I am aware of their low value, but still enjoy saving them.

Here are the bills (all FRNs). All notes are average circulated unless specified.

Hundreds:
34 A

Twenties:
28 (FRN #2 - NY)
34 A
34 C (poor)
34 D star (poor)
50 (poor)

Tens:
50
50 C
63 A (x3)

I will probably have some fun spending these FRNs (except the '28 $20.) What would you do with these bills? Spend or keep?

A bank nearby has a cache of old-style notes - however, most are of recent vintage, with only a few dating back to even the 50's. I asked them to check for any non-FRNs and "numbered" Fed Seal (pre-gold) FRNs, but there are none there.