ok, the main differences between the julian and new style engineer boots. All of this is just IMO...what I consider good you may consider bad and vice/versa. I am not a leather expert or a boot expert.
Julians I think are better made as far as detail and craftsmanship. The leather is thicker and stiffer-reminds me of some steerhide motorcycle wallets I have. Disadvantage- they just don't fit well. Even with years of use I doubt they would be as comfortable as the new style.
New style- more sleek and refined. The fit is amazing. The boots are lighter in weight. The leather is 4/5 as thick as the julians, but WAY, WAY softer. I don't know enough about leather to know if it is inferior/superior. The fit compared with the julians though is like night and day.
new on left, julians on right- you can see the new are more narrow, different heels, stitching is better on the julians
The buckles are sturdier on the julians, but keep in mind the leather is also thicker and tougher. I like the new buckles better as they are different than the usual style and I've only seen some like it on vintage boots. Notice the strap placement is different. The new style let's you strap in tighter to your foot. Both have double row stitching- notice it's very narrow on the julians and wider on the new style.
Notice the flaps are opposite. Julians on left- shaft is a little wider and about half inch shorter, natural leather inside. New style on right- shaft is about a half inch taller and more narrow, I can't tell if the leather is dyed on the inside or if it is dyed all the way through. Actually a reinforcement going up the back inside also
New style on left- heel is more narrow and has more of a curve. new style is more natural finish while julians are darker covered in more dye. Notice the julian sole is cleaner
New style on left, julians on right
logo is so generic on the new ones, nice logo on julians
again shaft is more curved=wider on julians
instep of the new style, again showing how narrow. They fit more like shoes than boots
instep of julians, not as curved of pronounced
Hope this helps. Like I said I like the new style better, I'm just hoping the softer leather will hold up for a few years. The julians are built like tanks, they just don't fit (ME) well