RG6 is just a generic name now. It's like 'size 11 shoes". Yeah, but size 11 shoes for what? Rock climbing is different to ballroom dancing or steel toe-capped shoes for a building site.
All 'RG6' tells us is basic info such as physical dimensions and the impedance (75 Ohms). It doesn't specify anything consistent about the materials used for say the shielding, or the loss charateristics etc. That's why WF100 is an RG6-sized cable, but the performance is way ahead of the generic RG6 sold cheap at builder's merchants, electrical wholesalers and online.
Webro WF100
Labgear PF100
Triax TX100
These are all good, 100% copper coax cables. You can't go wrong with these. If you want to buy something else marginally cheaper then go ahead. Just cross reference the materials used and the loss characteristics. What the specs won't tell you though is how loose the outer jacket is on some cheaper cables and how that can lead to the inner core pulling clear of the connection. Then you've got marginal/no signal so you spend (in cost terms) your time troubleshooting an issue that spending a fiver more on a bit of cable would have prevented. Cheap cables are not so resilient to wear, and alu-based cables die fast when exposed to moisture. Copper can get saturated - literally water dripping out of the end - and it will still work and won't corrode through unless perhaps in a seashore environment.
The maths here is simple. Spend a little bit more now, and save BIG in the future. It's a false economy to install cheap cable unless you either make a living selling cheap cable, or you're the guy going round fixing all the problems it causes.