leverage. by owning the stock you remain limited by your available funds, but with CFDs you can play at a higher level of capital but with associated risk.
in the scenario where you believe the market will go up consistently over time for a particular asset, you can claim greater returns in profit from going long with a CFD than holding a stock in your portfolio.
you also don’t need the stock to go up by as much to make the same amount of profits on a successful CFD holding compared to an equivalent stock holding (based on personal capital). the counter risk is that if things are going down and you made the wrong call, you can make a hefty loss much quicker.
Ultimately, CFDs are a faster way to see returns on your money if you have done all your due diligence and believe you know which way the market will lean by the next day/week. Had I enough earnings to max my ISA limit, I would likely start to put a bit aside in my CFD account rather than my Invest account since it would give me the opportunity to see the effect of my decisions on how much wealth I can generate for the future. Safe to say, I wouldn’t be doing very many trades, but they would be ones I feel very strongly about and could secure a hefty reward if right, profits being moved over to the INVEST account to prevent the position running out of control