It depends on what you're looking for.
Bounties: These are low-risk since you're earning tokens for completing tasks, but the rewards can vary. Sometimes the tokens might not be worth much, but it's a good way to earn without spending your own money.
Investing: Higher risk, but also higher potential returns. You’re putting in your own money, so if the project does well, you could profit big. But, you could also lose money if it doesn’t.
If you want to play it safe, go with bounties. If you're okay with more risk for bigger rewards, investing might be better.