Just an opinion but I find the bar handle much more attractive with the toothy head, than the "fat" Tech handle. Having my brass NEW w/ bar handle redone in nickel is on my Someday list.
I'm not the expert but I think 3 and 4 are actual NEWs. The others have different names like Norfolk, Belford, Smedley, etc.
Not sure. They may all have very similar or the same heads; it's the different model names I've never been up on. But 3 and 4 are actual NEW razors, as opposed to the earlier New Improved, etc.
I got some soap today from the Shave Shop. Supposed to be like Florida water scent wise. Made by Gingers Garden. I'll post a review later.....