First off, I would encourage any diver, any time, to take the GUE Fundamentals course. You are lucky that you have several excellent instructors right there in Sweden. As HBDiveGirls says, this course will give you a real awareness of what you are aiming for in terms of buoyancy control, trim, and overall proficiency in the water.
As to whether you will want to do this course in recreational gear or technical gear, I'd encourage you to make a decision about whether you really want to make the time and financial commitment to advanced diving first. This is probably in the end a minimum 10,000 - 15,000 Euro commitment when all is said and done. In my opinion it is difficult to be a proficient advanced diver at the levels you're talking about if you're doing less than 50 - 100 dives a year, and probably going out every single month or close to it.
A part of the commitment is physical fitness. Are you willing to put in the time to saty in the kind of shape that will help you efficiently decompress, efficiently metabolize oxygen, safely handle gas loads and pressure changes?
If you can answer yes to this, then get yourself in touch with a GUE instructor, talk about gear and gear configurations, and get what you need. Do a few dives to get somewhat familiar with your gear before the class, but not so many that you build any habits that will have to be undone later. Years ago, my first dive in doubles was the first dive of my DIR-F class. Probably not a recipe for getting the most out of the class.
As MHK says, GUE Fundamentals is not a class to approach as a "check the box" experience the way you might have thought of the course ladder in other agencies - something to get through quickly so you get on to the cert that gives you what you want. Rather, without sounding too metaphysical, it is a first step into a lifestyle choice. When you pass the course, techinically speaking you won't be able to do anything you couldn't do without passing it (no additional gases, no greater depth, etc.) However, you will have your attitude toward diving altered in such a way that you will never dive or want to dive the same way again.
My .02