I also drank a bottle of the 1998 Wynns Coonawarra Cabernet Sauvignon. This is an icon brand in Australia: it has been around for a long time (more than 50 years, I believe), is produced in large volume and at a reasonable price.
This wine tries to be an excellent wine at high producion volumes. It succeeds in part. The wine has a good structure and in good years, such as 98, it has good fruit concentration. It always needs time to settle and mature. This wine was still lively and has at least 5 or 7 good years in it. On the other hand, you taste the consequences of mechanical handling. The wine is not as harmoneous and rounded as those of good small producers.
The wine was enjoyable to drink, but not outstanding. The tannins were a bit harsh and require a good piece of meat as balance.