It's basically free money if you're willing to save it. Matching means that your 100$ investment immediately turns into 200$, which is a return that's very, very difficult to match, even with very good investments. Instant 100% return is very good.
There are only two circumstances where I'd turn this down.
1.) You're not making a lot, and you'd rather have the money immediately to pay bills, get education, etc. Something that provides a higher immediate return to your life.
2.) You are EXTREMELY comfortable with leveraged trading of volatile assets (Like you're a high end Bitmex trader) to the point where 100% returns on small amounts don't mean that much to you and you feel you can do better.
There are only two circumstances where I'd turn this down.
1.) You're not making a lot, and you'd rather have the money immediately to pay bills, get education, etc. Something that provides a higher immediate return to your life.
2.) You are EXTREMELY comfortable with leveraged trading of volatile assets (Like you're a high end Bitmex trader) to the point where 100% returns on small amounts don't mean that much to you and you feel you can do better.