feeling men tend to do well with thinking women, Ive noticed. Thats what you might be liking right now. The novelty also, the practical cut through the bullshit attitude of ISTJ's. She may be appealing because she is clean, she smells good, has her life in order, can cook well, is good in bed, is modest and proper, conscience and critical. Weither or not it can work is up to you two, and how developed and balanced you are as people. ISTJ's are mostly concerned with security and not going bankrupt, they can tend to have a lot of anxiety and imagine worst case senirios, they can have trouble taking care of themselves financially and be weak when it comes to showing how they feel in an emotionally vulnerable way. They can prefer to get angery and scared about life and tend to make lots of generalizations to explain away their fears. They are decent people, but You may feel like your mom is yelling at you all the time. Depends after the honeymoon period wears off.
Of course this is a generalization too, and I could be wrong, nothing is this simple to analyze when it comes to people.

oh, I said that already...sorry for repeating.