TL;DR. I won't use them again.
Yes. Quite extensively in the past actually, but not sure I'll ever use them again. Let me explain...
Perhaps six or so years ago I was keen to buy some wine on the secondary market. Sterling based in Perth was really advantageous as their office was one suburb away. This meant I could pick up directly any wine I purchased from auction. Be it just a bottle or two. Saved me having to pay the minimum amount postage and also meant I didn't have to worry about shoddy transport of the wine.
Back then there were some great bargains and reserves were realistic. As time went on I found there were fewer bargains and the reserves for wines of unknown provenance was simply not worth the risk for the asking price. I still purchased a few bottles here and there. Never really had provenance issues which was a good result.
Then they changed and decided no more pick-up. Wine had to be mailed out. However, they offered free postage for Perth. I thought that's reasonable still. Then they started charging for local postage which meant buying just one or two bottles at an auction just didn't make sense. I still got the emails and had the odd browse, but noticed reserves were high and the same wines were being passed in, auction after auction.
A good friend of mine has been buying from Sterling for a very long time. He too was disappointed with the changes but kept buying, until after one auction the wine posted to him just didn't turn up. Australia Post were useless. Sterling was not interested and essentially blamed my friend for not taking out the optional insurance on delivery.
Now my view and my friends is insurance isn't there for tracking down stolen/lost wine deliveries. It would be to deal with a bottle breaking in transit. My friend again approached Sterling and their attitude just stunk. Something along the lines of he is wasting too much of his time chasing up the issue and bad luck. My friend wasn't aware of credit card charge backs until I told him. He contacted his card provided and the charge back was completed. Sterling have lost a long term customer who has easily spent over $10k with them.
After that story, I don't think I'll touch them again either.
I've heard many good things about
https://www.wickman.net.au/ but not yet purchased there myself. I do like how they give some provenance information, which is more than Sterling do. I've had contact with the owner about holding wine for me should I buy and he seemed very accommodating.
Sorry for the lengthy response to what was originally a simple question.