I would only consider doing this if you already have a significant emergency fund saved up. If you find that you still have a large chunk of change that isn’t earning you significant interest, it could be a good time to put that money to work. Remember, if money isn’t at least earning enough to offset inflation (at least 2% or more), then it is essentially losing value over time. Better to put it somewhere that either earns you more (investing), or saves you more (decreasing debt).