Elixir Nanoweb 12057 Light 7 String

Pros:
-Corrosion-resistant, indeed. My sweat can destroy some other strings, even those, which also advertised as "corrosion-resistant". But these will last forever without any sign of tarnishing. I used these sets for 3 month max, though.
-Great high-gain tone, and long-lasting as well.
-Consistent quality. Never had an issue with them.
-Perfect gauges for drop C on 25.5" scale (if you'll use .56 as a sixth string and don't use .46 at all). Might as well work for other drop tunings on other scale length guitars.

Cons:
-Price
-I personally don't like the clean tone of these, it's too bright and rattly. Not like fret buzz rattly, but on their own. I'm talking about wound strings, plain ones are fine.

Even though these aren't completely perfect for me, I highly recommend to try these at least once, you might find your favorite strings!

I've used Elixirs for over 10 years now.

The tone of the strings is very good, being lively and present, and most importantly, consistently so over the lifetime of the string.

The string life is simply exceptional, with a set usually lasting me several months with regular play.

The string feel is also an important factor, with the wound strings being smoother in feel, and producing less finger noise than non-coated strings.

The only real downside is that if you pick hard, the coating will peel and fray in the section of string in which you pick. This can lead to a case of "dandruff", where little flecks of coating will break off and gather on the guitar between the pickups. It's irritating, but I make sure to wipe the guitar down after playing. Since this area of string is not one I typically touch with my fingers, it's probably not the end of the world the coating strips here; the strings still maintain fresh tone even when this area becomes frayed and worn. I'm willing to put up with this inconvenience due everything else being overwhelmingly positive.

So I've just changed the strings on my 7-string the other day. For the first time since 2011. I'm not kidding.

Granted, I'm not a touring musician, I only play at home maybe 3-hours per week on average. And my hands do not produce oils and acidic sweat (I'm one of the few).

But still, that's a lot to ask for a songle set to endure considering that play metal with a 1mm thick Dunlop Stubby pick which is pretty aggressive. After four years, the strings did show traces of use but they held on and kept the guitar's tunning stable and consistent.

There was absolutely no corrosion and strings were smooth. Mind, I took no extra care - no polishing, not even wiping the guitar's neck.

The biggest surprise came when I put the new set on. The sound difference (old set vs new set) wasn't that big. Sure, the new ones were ringing nicely but the old ones still sounded just fine to record distorted sound.

Highly recommended for any user looking for reliable and lasting string set.

Using on 7-string Ibanez rg7620 (stock dimarzi/ibz pick-ups). Home/rehearsals/performances. Several years ago there was no 7-string set available.

Pros:
1. Crystal clear sound. Once you try it - you'll never go back to other string brands.
2. Life-time. Few times more than other strings. Those strings keep this bright, new string sound for much longer then others.
3. Total "Price vs. quality" win.

Cons:
For such a fan of elixir strings - the only thing I could think of is lack of other 7-string sets with other string dimensions/sizes. Like .012-.068 7-string set for lower tunings.
i.e. this particular set string tension for extremely low tunings (like A or G) is not enough, IMHO.

TL;DR: Highly recommended for 7-strings with B/dropped-A tunings. Possible tension problems with lower tunings (like A or G).