Hey All,
I am expecting to complete N5 grammar in about 50 days which feels like a very comfortable pace for me, how did everyone find the other levels once getting into a streak/grove of learning?
Note… My only prior grammar experience were titbits from WaniKani levels 1-10
A little on the subjective side as there’s a big difference between being able to recall something vs. truly knowing the point and it’s nuances yadadada but I think it’ll probably go something like this
N5: A lot of just straight-up memorization re: rules, if you’re able to grasp them decently well then it may not sting too much.
N4: You’re going to start feeling the sting, would recommend the pace slows compared to N5. Things ramp up quite a bit.
N3: A lot of very “similar” (for lack of a better word) grammar points that will take awhile to really understand the similarities and differences. Expect a lot of ghosts for this. The good news is that these are common grammar points so you won’t really be in the weed yet.
N2: I’m roughly 60% through it, but so far I’ve found it a lot easier compared to N3. From this point + beyond someone much more advanced can chime in, but I have heard a few people on here say similar things about N2.
Just IMO for all of this obviously! As always, it’s not a sprint or anything, much better to be comfortable with what you’re learning vs. getting swamped at a few points and then not enjoying the learning process at all. Welcome though!! 
For N5 and N4, I will just echo @EdBunpro .
A lot of N3 grammar points are so common and used everywhere… even thought it can get a bit difficult, the frequency they are used in games/ manga / light novels makes them somewhat easier to comprehend.
For N2 and N1… omg, some points are really really common! … but there is so much nuance too… at least for me which can make things difficult. If the grammar points are rare in my media consumption, I am much more likely to forget them hehe. Things slowed down quite a bit as my vocab can’t keep up.
For me, it took me 2 years to 100% Bunpro. I already knew quite a bit and was just re-writing my notes. This is not important as everybody is different , some people have more free time etc …
My experience is the same. The things that trip me up most are the grammar points that are very similar in meaning. The other thing is the N2 and N1 sentences aren’t as fully developed as the preceding ones. You’ll get some things flatly wrong (esp. in N1) that really ought to have an answer hint saying that’s while it’s either right or close, Bunpro is expecting something else. I’ve been trying to report these as I come across them. I really hope the staff considers that helpful rather than annoying. I genuinely want to help make the product better for future learners.
I am sure they do think its helpful. It feels like the grammar hints, descriptions and links (between similar grammar points) have improved quite a bit over time. Probably it does makes more sense to get N5 to N3 in a more finished state before N2+ (its not great… but at the same time…)
Considering there are already 800+ grammar points, I am sure that their To Do list is quite ridiculous too haha
Its quite funny from time to time: I would try 3 similar grammar points BUT the 4th one which is being asked for is the one that I don’t remember!
LOL! I can’t count the number of times the exact same thing happened to me! 
Thanks all for the responses, I am looking forward to n3 the most, seems like the best bang for buck when it comes to reading
Nice! I finnished the last grammar point of N3 today, and I can confirm that it really has been the biggest jump in my ability to read! I can read suprisingly well now, even though it takes some time and my listening is not as good. I also started bunpro when I was level 10 at Wanikani, I think it is a great match doing them both at once! The kanji practice you get from Bunpro is really helpful.
Adding all points from N5 - N3 probably took about 1,5 years for me, studying somewhat seriously. Getting into N2 and N1 was a different story, there are so many points that are similar and nuances that you are bound to make mistakes because of… reasons. Not researching those reasons kept me bashing my head against ghosts for too long before actually looking up the differences. For N2-N1 I’ve sometimes only added maybe 6 grammar points in one month. Either way, maybe another 2 years for N2-N1 with maybe 40 points or so remaining on N1 today.