This class was SO hard. It is one of the hardest classes I have ever taken and it will probably be very challenging. That being said, Josh does everything in his power for you to succeed. There is enough extra credit to raise you grade 5% and there are midterm redos. Office hours are also really helpful.
I think my only advice for this class is even if you completely bomb the 2 midterms, talk to Josh and see where you are at in the class before dropping because the class is kinda curved in a way

Samani has really engaging lectures and the concepts seem easy in class..but the tests are absolutely horrendous. The first midterm is not bad, but the second, and the final are pretty much impossible unless you are already amazing at physics. He expects problems to be addressed in discussion...which you do worksheets on your own and in groups...so no one really teaches you and you have to figure out the concepts on your own. The class has to be curved an incredible amount because he literally designs his test for most students to get a majority of the questions wrong. The extra packets, discussion worksheets, and online homework are all things you do on your own and have no guidance on, again having to teach yourself the material. If you go to his office hours, he wants you to work it out on your own, which is fine, but he gives actually no help at all.
I do not recommend taking his class unless you have a physics background.

Cool Class. take it.

I've never really met Samani in office hours because I heard he wants you to figure it out yourself even if you go to him. I can say without a doubt that you'll probably end up with some sort of A coming out of this class. If you go to every discussion, submit all the problem sets on time (they don't even need to be correct), go to lecture to earn extra credit, score average on his midterms, and 8 points above the average on the final, that's an A. He lets you correct your midterm for 1/3 of the points back, and it's really helpful to go back and see what you messed up on. I came out of the class knowing physics more than I thought I would've.

Samani perhaps the clearest professor you can get. He is very capable of explaining new concepts in simple ways and emphasizes intuition rather than brute-force math in his physics problems. It's been said that Samani's exams are harder than other physics professors, but I've never really had an issue with them. If you managed to get past the AP Physics 1 exam, you should be able to get past his exams just fine. Which is convenient, because Physics 5A is just regurgitating AP Physics 1 material and nothing more. If you've taken AP Physics 1 before, you literally will not learn anything new.

Professor Samani offers extra credit for hard work, so it's very easy to pad your grades even when you perform poorly on homework and exams. He also grades a lot of the homework on effort and completion rather than accuracy, so grades (other than from exams) should not be a big issue.

One thing to watch out for, though, is that he wants you to check a multitude of websites for announcements and homework, so things tend to get lost in the clutter.

Overall, Samani is a fantastic professor and I would highly encourage you to take his class over other physics professors' classes.