Whilst I would simply regurgitate whatever my Salafi...
Whilst I would simply regurgitate whatever my Salafi brothers had taught me - he would always reply logically and would back up his comments by citing traditions from classical works such as Sahih al Bukhari. In truth I had not discussed any of these conversations to my Salafi brothers, until I was out one day and visited a market stall that was run by two Salafi reverts.
After our general salutations I informed one of the brothers that I had a friend who was Shi'a and inquired whether he knew anything about the Shi'a faith. No sooner did I say the name "Shi'a" that the brother's face changed colour, he said: "Brother don't talk to them they are kafir (infidels), they believe that the Qur'an has verses missing".
I told him that the Shi'a I had spoken to denied this and countered me by presenting a tahreef tradition from Sahih al Bukhari - with Umar stating that a Surah on stoning is missing. The brother was shocked and after about a minute's silence he said: "brother they did black magic with your eyes you didn't see it!" This really made me laugh and I walked off.
I proceeded to do my shopping and was just passing the stall again when the brother called me over and introduced me to a revert who he acclaimed as an "expert on Shi'aism". The 'expert' said: "So you wanna know about the Shi'a kaafir, all you need to know is that they believe in 12 Gods". Even I from my general conversations with the Shi'a brother knew that this was a blatant lie.
I then decided to test him by quizzing the fact that Shi'as believe 'Ali to be the Prophet (s)'s legitimate successor and I cited the Sahih tradition 'Ali is to me as Harun is to Musa except there shall be no Prophet after me'. The 'expert' then countered this by asking: "And what did he (s) say about Umar[r]?" I knew exactly what he was asking and said: "If there had to be a Prophet after me it would be Umar". The expert patted me on the back and said: "Exactly brother".
I then asked him "That being the case why did Umar not become the first Khalifa? Is this not an insult to Hadhrath Umar?" The expert looked bemused, smiled and said: "Brother you've just used your Aql (reason) and that's haraam". It was that reply that will act as a permanent memory for me. I still remember looking over to the revert brother who owned the stall following this reply, he smiled a half smile, that to me suggested that he was about as convinced at the reply as I was.
For me this was the turning point in my life.