Position- Software Developer in Test (It's for a specific team)

I am interviewing for SDET position at Mathworks. I wanted to share my experience and also wanted to know if anyone else has gone through the Mathworks onsite interview process.

Round 1- Phone round
I had a call with the Project Manager. He asked me some resume related questions and a lot behavioral questions. (Duration: 40- 45 mins)

Round 2- Technical phone screening
This round was with a senior engineer from the team.
I had to write code for 'Palindrome'. I wrote 3 solutions-

1. Reverse and check 2 strings are equal
2. Pointers at the start and end of the string. Keep checking until you reach the center.
3. Recursive
   As this is a SDET position, I was also asked to write testcases for the code and execute each of them. (Duration- 30-35mins)

After the coding round, I was asked basic OOP questions, questions related to garbage collection in Java, few questions related to JavaScript. (Duration- 30 mins)

Round 3- HR round
Questions like Why Mathworks? Salary expectations? etc.

Final round (Onsite interview)
I have the interview scheduled next week. So I wanted to know if anyone has given an onsite interview at Mathworks? I would really appreciate if you can share your experience.

The onsite round is a 6 hours interview.
--1 hour presentation in front of the whole team (ppt about myself, my work exp and a project of my choice)
-- 3 to 4 one on one interviews with the team members (45min each)
--1 interview with HR

I am really nervous about the 6 hours interview and would appreciate any kind of help. (especially about the presentation part)