Assalamu-alaikum
Assalamu-alaikum sister,
MashaAllah its good to know that brother Imad is concerned now that where you taking your knowledge of deen from. To me his concerns are very genuine and reasonable.
His advice was really important that you should look for proofs from Quran and Sunnah.
Sister its normal that we all have this tendency to be inclined towards something which we know better ourselves, like he knows well about Sultan.org so he suggested you that likewise you will suggest many that they should come here at TTI.
Now, the difference between the two sites is that one (TTI) is an active forum and you can ask about anything specific that is your concern at the moment whereas other one is knowledge bank but you cant communicate there.
What you should take care of, whether be it TTI or Sultan.org is that it should have a backing from the Quran and Sunnah.
May Allah make your learning journey a pleasurable one