I have ~9 years of experience and working with avg product-based technology company. I have been giving interviews for a while for the Bangalore location, I've had wonderful and bad experiences with companies/HR/Interviewer so far.
I would call an interview experience wonderful when even though you are rejected but still would like to go through the same process again in the future.

ServiceNow : I got a chance to give only one interview and it went fine as per me, I may be biased. But, I could sense that interviewer was a junior engineer and he was planning to ask 2 questions. Both were leetcode(easy/medium) and luckily I was able to code the first one with an approach within 15 mins and the next question took 12 minutes. Those questions were really simple, I am not being immodest (I have been rejected many times lately).
We discussed my roles and responsibilities in my current company for 5 minutes and then he asked me another standard question from leetcode and I was able to code that up as well in 10 minutes. He said that this is the first time he was seeing this solution, then it took 5 minutes to convince him that it will work.
I felt happy about myself. However I never heard from HR since then, I even sent a mail asking about feedback and where I went wrong.

Nutanix: After clearing the online assessment test HR scheduled a discussion. On the interview day, just 1 hour before the discussion received a call from HR stating the interviewer is unavailable. they wanted to reschedule the discussion for the next day and I requested to schedule next week any day. That's the last I heard from them. After 2 weeks I sent a reminder mail asking about scheduling the discussion, within 30 minutes I received an automatic rejection email.