A while ago we had some light switches and power points changed to Clipsal Saturn, the electrician was on about the old switches were cheaply made, he would never use them, he only trusts reputable brands. I was happy to hear that.
The next time we called him to change a breaker and to install a 15A power point in the garage (for an air compressor), he took some generic looking GPO from his van but we weren't too fussed as it was in the garage. I didn't think of asking at time, assumed he only use quality components. But later I was curious to find out what are the good brands he was bragging about and he would only use those brands.
Quick Google found out they are AS compliant alright, but cheap cheap cheap, what a hypocrite! He never asked what we wanted nor quoted different prices for generic and name brand parts, he just came with the cheap parts. The first time we specifically wanted the Saturn so he brought those along.
Probably unusual for people to ask specific brands, so it would be up to the sparky to decide, perhaps many would just use generic parts to drive profit. Does your sparky give you an option, do you have to ask? Or you buy the parts?
Were they driving an LDV ute?