I believe JoeCab is correct - Sumitomo owns Dunlop.
I can give you my experience with Sumi's: The rear tires on my 993 were nearly worn out and I had also been reading rave reviews about Sumi's on a p-car forum. When I checked the price of just two Bridgestone SO2 rears they were more than the cost of 4 new Sumi's, so I decided to take a chance on them and buy the HRT Z III's, so my experience is specific to them. I've put about 1500 miles on them and have been completely satisfied - first, you can't beat the price; second, their dry and wet performance is great - they seem to perform just as well as the SO2's. Unless you track your car and actually push your car to the
limit you won't notice any compromise in handling - they seem to perform as well as
SO2's or Michelin Pilot Sports; third, they have a much quieter ride than my previous SO2's; and lastly, they are reported to to give much longer life. I got about 14,000 miles out of my SO2 rears (more than most 993 owners get out of them) and I've talked to other 993 owners who are at 15,000 mile on the Sumi with little noticible tread wear.
I've liked them so much that when the 360 needed tires (same situation: rear PilotSports worn out) I decided to risk being excommunicated from the Ferrari Club of America and give the Sumi's a try on the f-car given how impressed I was with them on the 993. My experience on the 360 has been the same - fantastic tires. Quiet, great wet/dry handling, and hoping for longer tread life. I've only put about 800 miles on the sumi's on the 360.
Regarding Alfa Romeo: My '91 Spider needs tires and come Spring I'm planning on putting a set of Sumi's on it too. The smaller size means using something different than the HRT Z III's but I figure if they can make a wide, low profile high performance tire they can probably handle making a smaller 195/60 X 15 tire. I don't recall the specific model Sumi makes in that size (HTR, I think) but I checked and they're only about $50 each - if they're as good as their high performance tires, it's a bargain.
I have read that Sumitomo is trying to gain a foothold in the US and this may be why their tires are priced so competitively. However, I don't know if this is fact or fiction. Regardless, their tires seem to offer incredible value for the money.
Cheers.
