I'm thinking about getting a pair of lineman's pliers to add to my toolbox. Should I go cheap and get a set from Harbor Freight or spring extra and get a pair of Channel Locks/DeWalt/Milwaukee?. I know Klein's are the gold standard but they are just too expensive.
My HF lineman pliers seem to be working just fine for me.
In my opinion Linesman's are all about cutting. I might use the pliers part once a year. Were I to replace mine it would be with a 10" diagonal cutter
My 9.5" Klien Linesman's are 15 years old and still going strong with only one knick in the blade. Amazon has 9" Kliens for $29. IMO Channelock tools feel crude and heavy but they are a great value for a USA made hunk of steel and will last forever. Amazon has the 9.5" for $21.
I am a Knipex junkie so I would pay the premium for them.

Choice 3: Napa Pro from Cripe Distributing.
My youngest daughter gave me a pair for Christmas that she bought for $1 at her school's holiday shop (likely from HF or similar). I don't have any complaints but have only used them twice.
Yard sales and swap meets. Look in those boxes of $1 tools. Lots of junk, sure. But you also find some treasures. Beware, you will find all kinds of tools in those bins and boxes that you had no idea you needed. I've probably got 40-60 different types of pliers and such. All different, all wonderful.
If all you're going to work with is copper wire, anything will do. But if you're thinking fencing and such, you want a good tool.
I'd buy the HF and pick up a nicer pair if one comes up at a good deal or the HF pair actually breaks.
Should I go with a pair of 8' or 7.5'?
Choice 4: Kobalt from Lowe's
How about 2 pliers in one??? Alltrade pliers - Lineman pliers and diag cutters in one tool

I'm cheap and I own a pair of Klien linesman's and diagonal cutters. They must be getting close to 30 years old now.