I am an FFB. When I was in Yeshiva way-back-when there were many BTs. Many of the BTs were friends of mine and really enjoyable to be around, however I don’t think I 100% understand all of their ways. I coined the term “more religious than thou”. Many shidduch offerings were not ‘religious enough’ for them, but were somehow suitable for other FFB yeshivish guys who became engaged. Disposing ALL of their colored dress shirts (I didn’t need to go shopping those years). Not wanting to EVER return back to their non-religious home, although they said their parents were respectful and accommodating- dismissing the option of purchasing their own frozen meals and walking to their nearby Chabad on Shabbos. —- Sadly 10 years later, (according to social media) many of these men are no longer religious at all as the pictures reveal bar pictures on Friday nights, no yarmulka, way of dress, type of men/women they hung out with, treif restaurants, etc.
Concluding, life can be very hard for a BT if they don’t maintain reasonable accommodations for themselves and appropriate goals & expectations, as I’ve seen it becomes an “All or nothing” 5-10 years later. No one is going to become the Chofetz Chaim overnight, regardless if one is a BT or FFB. Better to wear the blue dress shirts on Tuesday than to expect to know all of Shas by the summer. Thus, I believe FFB has IT easier than a BT.