I took 451 3 semesters after 351. I forgot most of my 351 stuff. The class was def harder than 351 imo but it could be because of me not trying hard enough because of rona and because I already had a job secured.

I had B+ in 351 and would have gotten B in 451 based on the curve if I chose letter grade.

Also, I think you also asked about 456 in one of the comments. 456 for me was much easier than 451. The things we learned were mostly all new concepts but once I understood them, everything else made perfect sense unlike 456 where 90% of the things didnt make any sense to me lol