May i know when should i transition my lo to a straw cup and what are the benefits? I read sippy cup is not recommended. which straw cup is recommended?

I latch my boy for his milk. he drinks water using the straw bottle, much faster than using the sippy cup. I decided to switch to straw as I learnt that it is more intuitive (which happens to be true!). I didn't even have to train him, he just sucked the water through the straw.