As someone who switched from a Walmart bike to a carbon fiber bike I can definitely say there’s a huge difference. Everything on the carbon fiber one is much higher quality. The gear ratios is has make sense, whereas I could never find the right ratios on the cheap one. Switching speeds is much faster too as I can be pedaling hard while changing gears and I know it’s going to do exactly what I tell it. Finding parts is very easy compared to the Walmart one. Anytime something broke on the old one it was difficult or impossible to find a replacement. With a much nicer bike you can get parts for it easily so I can keep it in top shape for a long time. There are many other benefits as well.