Earlier quoted context omitted.
I mean this is a terrible investment no matter what. 3% interest that, let's be honest, there's serious doubt as to whether you'll actually see? From an investment standpoint it's the lowest of junk bonds without a particularly high interest rate either. There's a million things with both better upside and safety.
Nobody invests in convertible notes for the interest. YC's SAFE is basically a note sans interest. Investors looking for high interest rates on notes should be a red flag to startups as well.
The only benefit for this early investment is the 8% discount. It doesn't feel like a fair trade for the added risk of investing earlier.
All that said, it's nice to be able to have the outside possibility of future return for a donation that supports their mission.