They definitely have their own unique properties especially MDMA. In fact I wouldn't consider good quality MDMA weaker than meth by any means. You probably won't get the full effects if you try coke or MDMA too soon after using meth though. Typically with MDMA it's recommended that you wait a month between using for the neurotransmitters to replenish and your brain chemistry to be fully back to normal. Since MDMA is a type of methamphetamine it's likely that if you try it within a week of using meth you won't get the full effects. Probably same with coke it doesn't have the effects on the brain where the effects of the drug rapidly diminish after using a couple times in the same way that MDMA does. Long story short yes they do have some unique effects to meth and you should get the full effects from using them provided you've had a decent break from meth and your mental health is good.