Hard gel brands do not soak off, so if it's very important for you to soak off the product then you will have to choose something like L&P, or perhaps polygel (not sure if that soaks off?). I know there are some gels that soak off, but I don't know of any, and the hard gel brands out there (CND Brisa, Light elegance, young nails, and more) do not soak, they need to be filed off, with a thin layer left (youw ould learn this at your course). Either way, hard gel is easy enough to remove with a half decent e-file, so that should not really be your ultimate priority anyway
I use CND and recommend their Brisa Gel, strong extensions, I do not have any problems with them breaking, and my clients love long nails. But as swith many other brands, it doesn't soak off.