> They are reliable enough but not exactly perfect. It’s pretty common to have the chain slip off. It should not be common for a chain to slip off, something i

> They are reliable enough but not exactly perfect. It’s pretty common to have the chain slip off. It should not be common for a chain to slip off, something is wrong. The something may just be parts quality. Derailers are a case of getting what you pay for. The cheapest ones are junk and will never shift well. My partner bought a bottom quality bike with no-name shifters and it has never shifted correctly from day one. It does also drop the chain. No amount of aligning will get it to shift well. In contrast my 18 years old mountain bike with Shimano XTR derailers has always shifted perfectly and still does. Bike derailers is one area where it's definitely worth it to go for top of the line components and never worry about it again. Low quality components will make you hate they money you saved every single time you attempt to shift.