Also, let’s be clear- the process of trying out modules and learning eurorack is not something that comes without substantial cost- I don’t even want to think about how much money I’ve lost from how many modules I’ve bought and later sold at a slight loss/shipping costs, and that’s with buying used as often as I can. I also did that whole exploring thing for like two whole years before I finally settled into what I’m using now, which is a pretty silly amount of time to spend figuring out an instrument, now that I think about it.
It can be really hard and oftentimes frustrating to figure out what actually works well together in a system. The pre-built system is one curated by manufacturers who know their modules better than anyone else, obviously, so you get guaranteed system cohesion and focus without the vast costs of both money and time from constantly buying/selling modules to find what you like.
Having gone through it all, and knowing what I know now, if I had to do it again I’d buy a manufacturer system like the Make Noise or the Endorphins, and for the people who have the money upfront who want to get into eurorack, that’s honestly what I’d recommend.
Though it depends on what your goals are- if you want an actual focused and cohesive instrument for making recorded music, which is what I eventually realized I wanted, then the pre-built is great. If you just want to play with sound in a vacuum and aren’t really concerned with making recorded music, and if the experience of piecing together a frankensynth actually appeals to you, then do that.