Hi mate, I would say it is significantly harder than L2, there was basically very easy maths in L2 and the principles/formula's were usually only containing 3 variable so very straight forward.
The 301 exam (40 questions) sylabus is absolutly huge and rattles along at a fair old pace, it takes about 10-12 weeks just to do the maths/circuitry and thats before the months and months of motors, motors, motors and electronics.
You will learn and know inside out:- Inductive reactance, Capacitive reactance, Impedance, phasor diagrams, power factor, inductance and capacitance connected in series and paralell, general series, resonance, DC circuits, 3 phase calculations, star feeding delta and vice versa, and thats just in the first 10-12 weeks, and thats just a small part of one unit.
I'm not trying to put you off, but the difference is very noticable, I got distinctions in all 4 of my L2 exams and although i'm coping ok, I'm having to work hard at it.
Good luck