Not sure about either one of those. I have heard of Nolan, but have no esperience with them. I aure some old fart will give me a fit about this, but Simpson has a fine kevlar, Snell rated full face for a shade over $200 available on line, directly from Simpson. I have one, but when I bought mine, they were $300. Its called the "Fury." It is lightweight and wind noise is minimal. It also seals well on the occasional cold day we have in SOFLO. You can get a smoke colored shield for it, and the shields will interchange in seconds. There is another one called the Avenger, but it is heavier. At Wally's, you can buy a full face Bell that is DOT rated for under $100.
I think its a matter of personal preference and comfort. IMHO, they will all protect but none are idiot proof. Since they all have to pass certain standards, much of the price difference is in the quality and durability of the soft parts anyway (straps, lining, etc.)
As a practical matter, if you strike something so hard with your head that there will be a noticable difference between an inexpensive helmet and an expensive one, chances are the only ones who will know about it will be your heirs.