I'm an EII, 4w5. I've studied Socionics for about 8 months (as of this post), after switching from MBTI, which I'd studied for 3-5 years. Socionics seemed abstruse and difficult to learn, unlike MBTI, which abounded in cute infographics. However, I'm delighted to have transitioned.
Socionics is far better.
PS: I also forgo translating between Socionics types and MBTI types. Translation's quite a common fallacy, isn't it? It saddens me, to behold an MBTI veteran read nothing about Socionics, yet confidently equate two types.
INFJ ≠ INFj ≠ INFP
Have a nice day, everyone. You might see me around, sometime.