It was a great experience till I got to the third round.
Process was as follows:
I got a call from their end.
First Round - I had to submit one Online Assessment.
Second Round - DS/PS, JS basics etc
Third Round - Framework related questions, JavaScript basics etc

Then at least 2 weeks of gap in which I already got offers from Amazon, Paytm and Tekion so I was giving interview just for the sake of it because this was one of the first companies I was approached by.

This round was whole lot more than just unprofessional.

• Firstly there were multiple reschedules from the interviewer's end.
• Secondly he was using mobile data to interview due to which I wasn't able to even listen to one question clearly(neither did he want to fix it).
• Thirdly, Interviewer was from some BITS (Goa/Hyd I'm not sure) and I know this because he started with COMPARING HOW HE COULDN'T get into IIT but I did. It was more than just clear that he is somewhat gonna come to this again which actually happened whole throughout an hour.
  It was an hour of just putting up a question and then trying to mock me till the time I get to one solution, in a very rude manner. Although this has happened to me before so I was able to hold myself and crack through almost every question(I was able to hear from his end).

TBH I have interviewed people in the past mostly from Tier 1 colleges but every time we had to, our employer specified some ground rules to make sure none of the interviewees suffer even if they are at their worst.

Last words: I was too excited for the interview because of the hype which is there these days of best in terms of work culture but this interview put me off.

An interviewee is as important in a process as the interviewer. I don't think there is any right for anyone to be rude and unprofessional.
Also, if a person (at least 25 years of age) is behaving like 12th class student, it's more than just being toxic in terms of work environment. I'm sure if this has happened to me then it must have happened to others as well.
I would any day prefer a company with bad WLB but quality and supportive people than just being in toxic environment. I hope you get the talent you deserve but don't bring your childhood trauma's of being in some X college not able to crack some Ys to make a hell out of some person's life because in longer run he/she might be a great asset to the company.

Also, BRING IN THE INTERVIEWERS WHO KNOW THE ANSWERS TO THE QUESTIONS THEY ASK.