If I recollect correctly the WTC came over to the UK in numbers circa 1992. Now Simmons may well have been marketing scopes in the USA earlier, but these WTC were a hit in the UK from about then.
What was good about them, other than they looked great, was they had a higher build and some great glass for the budget market.
There had been quite a decline in quality of budget scopes in the late 80's/early 90's. Tasco only had a couple of good scopes in its line, though it did bring out its Euro line. And everything else was all over the place and not much was that good. Far too much just rebranded old tat, or just done cheap.
Not many shooters could reach for Leupold or above, so these WTC were a joy.
Simmons did have some real success at the beginning. They even brought out some higher quality offerings Aitec??than the WTC's, though these were heavy. (bought one sold it.)
I remember they brought out the diamond reticule. I bought one and gave up after returning three as non would hold zero throughout the zoom range.
Tasco went down hill from 1995, as did Simmons. Deben was the agent.
I had the 1.5-5x20 on a Theoben Fenman for many years. For some reason it has a real following, and still demands a premium. I don't really know why. I sold mine as I preferred my 2-7x40 B&L for this rifle combo as the glass is so much clearer. Leupold does a better scope of this type/style but then is a lot more money.
Yes, WTC are fine budget scopes. However, they are showing their age. The glass really isn't that clear anymore, if it ever really was. I probably had ten on various combos over the years, but always eventually moved them on for something better. Definitely worth having a few examples in any collection.