The consensus here through many many threads is this is the MOST critical wrench to have the best on. Reality is most pros could get by ok with second tier wrenches, and surely sockets, screwdrivers and such. But a few critical things like torx bits, hex bits, line wrenches and other items where small areas have tons of stress are the way to go. It's a small list...but worth it...100% if you are a pro. Think Snap-on...or maybe other top shelf.
The flip side of the Cliff Notes is don't bother with cheap import ones at all. Just don't. They are fine for big heavy wrenches....but not here.
The middle of the road I suppose is ok if not dealing with rusty or other ugly situations. I have SK in metric and I have found them great....but never have had to deal with nightmarish fasteners for them. Have Craftsman RP USA and seem ok as well for my needs. I assume Armstrong is in the same league as these. Ok for home use or occasional use as a pro maybe dealing with newer warranty work such as a dealer shop. But line wrenches are one of the few VERY FEW items I would say spring for the top shelf stuff on if you are working as a pro for reasons beyond warranty ease. Old threads see some complaints about SK spreading...as well as other mid brands.
...I think any pro, even if not needed maybe, should have the absolute best wrenches with open ends....lines being the most important....hex, allen, tripplesquare and maybe a few items I am missing right now. Everything else...just better warranty, easy payments that will make those items shine and worth the cost. Good choices on stuff like Armstrong, SK, Craftsman, Proto and even some Harbor Freight will serve a pro just as well at a fraction of the stupid SO prices. But yeah....don't cheap on the line wrenches....just don't.
now if you find those at a swap meet or something they're probably a good pickup but as with many Cman wrenches there is essentially no warranty as you won't get anything similar if you break one. So if buying new I'd go to the source (SK) for the warranty.