IOTA isn't designed to be a currency per say. Their team suck at designing a user-friendly wallet, because they are mainly engineers and mathematicians who are focusing on the IoT aspect of the technology.
But on the front of adoption in real-world IoT use-cases, IOTA is actually making very impressive progress!
If you want a coin that has zero fees and fast transaction that is designed to function as a currency coin only (and nothing more), then go for Nano; which its aim is to compete with BTC but cannot be used as a IoT bridge like IOTA is designed for.
User friendliness does not have much to do with bugginess. You could have a super unfriendly wallet and as long as there are no or very few bugs, we can be OK. Look at byteball, similar DAG technology but they have been having a superb, hi tech wallet for ages,,, that is incredibly simple to use (if someone like me can use it, it is easy). Or look at Waves and see how the Lite wallet version is also so beautiful and easy.
I do not buy engineers and mathematicians cannot make bug-free wallets.