The presessional addresses topics that are relevant for mathematical finance, regardless of where you will study.
As a standalone, it kind of depends on 3 things, in my opinion:
1) how deep you are going to study Math Fin
You can learn stochastic calculus as it is exposed in Wilmott's book. It is not very rigorous mathematically speaking. It is more intuitive, so the pre-sessional would not add much. However, there is a lot going on in the background that you are not aware of and when your interviewer asks you what is the quadratic variation of brownian motion and asks you to prove it, you will not even understand the question properly. This question was asked to an acquaintance of mine in a real interview. So it depends on what your goals are in terms of depth of knowledge. The contents of the pre-sessional are pre-requisites to understanding more complex concepts which are directly applied to math fin.
2) Your current maths knowledge
The contents of the pre-sessional are available in books, so you can learn by yourself if you can. I was not at a level that I could learn by myself. The pre-sessional helps in the sense that you have contact with the tutor, which is extremely helpful and because it is friendly in the sense that it starts from a point that is not extremely complicated, so you can build your knowledge step by step. That being said, it was still challenging to start the MSc as I felt there was still a small jump in complexity (specifically in probability theory/measure theory).
3) No time "wasted"
It focuses only on the stuff that is needed for math fin, so there is no time "wasted" with things that will not be needed. This is also true for the MSc. For instance, measure theory is a huge field. They teach you what is relevant for math fin only, so no time is wasted with stuff you will not need.
Bear in mind that a lot of math fin is a bit niche, so it can be very hard to find useful information online at the level that someone that is learning can understand. When you find something, they are usually questions/answers in forums which are written in such a way that is super hard to understand (at least for me it was). The answers are usually the same thing you read in the book, which you didn't understand, which is what prompted you to search for info online in the first place. So, usually, not very helpful. I am aware of Stefanica's primers but I don't have them, so I'm not sure if it falls under this category of "things that are initially exposed at a very complex way, so it doesn't really build your knowledge step by step".
Not sure if the above was helpful. I hope so.
@danielryreYou are provided with:
1) Lecture notes (books, really): I like them a lot. Takes you step by step, from simple to complex, with examples, proofs, references, etc. Focuses only on what is relevant for math fin. This is the main thing I use to study/learn
2) Lecture slides with embedded audios: has the same content as the notes, sometimes with different examples etc. To be honest, I don't really use these as the lecture notes are really enough for me
3) Exercise lists: exercises to help you put to practice what you have learned. They are not easy and good luck finding answers online (you won't, trust me). You need to solve them yourself and this is where you really really learn, in my opinion. Basically, you won't manage to solve the exercises if you didn't really understand what is in the lecture notes, so this is the real way to check if you really learned.
There is a period for solving the exercises, where you can ask questions in the forums, by email, on skype sessions with your supervisor, etc. Then after handing over your solutions, you get it back with commentaries from your supervisor along with the worked solutions (Step by step so you can follow the rationale). After that, you have more time to study the solutions, go to the forums, speak to the professors, etc. And then you have the assessments.
In terms of how many hours per module, it's hard for me to say since I didn't really pay attention to that. I'd say it was very intense in the beginning, which is where I was learning to think mathematically. Afterwards, it became easier, so less time was required. The lecture notes are not huge, but they are dense. By that, I mean that you don't have thousands of pages to read, but, since they really optimised the content (they only include what is relevant), every word in the notes matter.
The assignments/exams are super fair. By my experience so far, if you manage to solve the exercise lists and really understand each step of the solutions, you are good to go. But bear in mind, the exercise lists are really challenging.
One thing that I like about the exercises (and exams) is that they make sure you are always solving relevant problems. By that, I mean that you may be solving a problem in an exercise list and, although completely unaware of it, the setting of the problem actually describes an up-and-out call option, for instance. You don't really know that, but that is the case.