It depends on the ROA of cocaine and meth. I have done a lot of both in the past, but for me, using good cocaine IV is the best euphoric high,although shortlived, of any stimulant. I have given meth injectors coke that they injected , the same amount I injected, they were so high off the injections of coke they had to go puke and were loving the rush, and these were long time IV meth users, who get easily inject a 1/2 gram of highly pure crystal from Mexicans and be ok, spun out but ok, no puke or rush like coke..But I would not advise anyone to IV any drug, or use cocaine or meth, as they both can and do lead to many problems , especially legal wise,....I much more enjoy the euphoria of opiates..