I used to trade stocks exclusively but started trading Forex a few years ago.
In my experience I've had both success and challenges across both asset classes. My advice is not to give up on any one asset class but find a place in your portfolio for it for diversification or risk management, in my case I use a trend strategy on some Majors which are negatively correlated with some of my more high 'Beta' stocks... usually helps me hedge in the highly volatile periods but also provides good upside over the trend...
In my experience I've had both success and challenges across both asset classes. My advice is not to give up on any one asset class but find a place in your portfolio for it for diversification or risk management, in my case I use a trend strategy on some Majors which are negatively correlated with some of my more high 'Beta' stocks... usually helps me hedge in the highly volatile periods but also provides good upside over the trend...