From Yasir Qadhi Facebook page

"There was a time in my life where I viewed advanced and abstract theological issues as being of primary
importance in the life of a Muslim. At that stage, l would have no qualms categorizing other Muslims as
being 'misguided' simply because they might have
understood a theological point differently than l did.
As I gained more knowledge and experience, l came to
realize that what is truly important in the life of a
Muslim is not the memorization of an abstract creed,
but rather the down-to-earth, raw, genuine love and
fear of Allah in the heart of a Muslim (or, to be more
precise, the Quranic terms of iman and taqwa).

What is important is not what a Muslim is taught by a
mainstream school of theology, or even the sect that
he/she is brought up in. What counts in the eyes of
Allah is how much you truly believe in Him, and how
much you demonstrate that belief in worshipping Him
and obeying His laws, especially with His creation.

There are righteous servants of Allah in ALL mainstream historical lslamic sects, and yes, while it is true that some sects have less 'problems' than others,
again, in the end its not adherence to that sect as much as it is allegiance to Allah and His Messenger that's important.

Initially, theological creeds were meant to defend
Islam and to protect the heart of a Muslim against
ideas that might be detrimental to them. However,
over time, most sects have now taken their man-made
and historically developed creeds as being the
ultimate criterion of dividing fellow Muslims. In the
process, these creeds have then caused arrogance,
division and contempt to grow in the hearts of people,
rather than humility, unity and compassion.

That was never the purpose of Islamic theology. Love Allah, and look upon fellow believers with the eye of compassion and mercy, and wish to benefit and guide all of mankind. This is the message of all the prophets, and the essence of true theology."