I use only D'Addario Strings. They have many sets of regualr strings and only a couple of sets of pure nickel. Here is what they have to say about them.
"D'Addario XL Pure Nickel strings look back to the '50s, when nickel was the primary alloy found in electric guitar strings. Into the '60s, these pure nickel strings would be supplanted when guitarists required brighter tone and enhanced magnetic properties/characteristic of the D'Addario XL nickelplated steel string line, Pure Nickel delivers classic, warmer timbres that define many genres including blues, classic rock, rockabilly, and more."
D'Addario does not have much of a selection in sizes for the pure nickel so I think a lot of guys don't bother with them. I think the gauge of the strings would make more of a difference than the construction of the strings.
The Blues is alright!
Guitars: 1968 Gibson SG, 2005 Gibson SG Standard, 2006 Gibson LP Classic Gold top, 2004 Epiphone Elitist LP Custom, 1996 Gibson Les Paul Standard. 2001 Epiphone Sheraton II, 2007 Epiphone G400.
Fender Strats: 1996 Fender 68 Reissue CIJ, 2008 Squier CV 50s, 2009 Squier CV 50s Tele Butterescotch Blonde
Amps: Blues Junior Special edition Jensen in Brown Tolex with Wheat front, 65 Deluxe Reverb reissue,1970 Sonax reverb by Traynor, Avatar Custom 2/12 Cabinet with Eminence Legend V1216 speakers,
2008 DSL100 Marshall Amp , Fender Super Champ XD,Fender Vibro Champ XD
Effects and Pedals: Fulltone Fulldrive II, Fulltone OCD, Fulltone Mini Deja Vibe, Fulltone Fat Boost, Dunlop Crybaby Wah, Boss DS1, Boss DD20 Giga Delay, Boss TU2 tuner, Boss BD2, Ibanez TS9 Tube screamer, Zoom 505. Radial tonebone hot british.