Srila Prabhupada once said that spiritual life is 90% common sense. Most things just follow a natural line of thought. Once we understand it we can understand the reason being everything.
There are always small differences in explanations, since different individuals will never explain things exactly in the same way, but all bonafide acaryas agree in the main conclusions, Krsna is God, we are His eternal servants, devotional service is the perfection of life, etc.
There are also spiritual teachers who may not be completely perfect, and thus may make mistakes, but may also speak mainly according to correct conclusions.
Ultimately, it is not up to us to judge and compare. We should find a spiritual teacher we trust and follow him or her, that's all.
There are always small differences in explanations, since different individuals will never explain things exactly in the same way, but all bonafide acaryas agree in the main conclusions, Krsna is God, we are His eternal servants, devotional service is the perfection of life, etc.
There are also spiritual teachers who may not be completely perfect, and thus may make mistakes, but may also speak mainly according to correct conclusions.
Ultimately, it is not up to us to judge and compare. We should find a spiritual teacher we trust and follow him or her, that's all.