Keep in mind all quality strops do the same job. No matter the critter or the finish. The difference is in how you feel about it and the luxury mindset. Also they will have a different feel as you use them as well as when you look at them.
I have a #3 and its a fine strop.
TBS has put in the time to be an authority. I have used lots of different surfaces to strop without my discerning any differences with the results.