Hi Corona,
I just went through this myself and did a lot of research -- mainly reading through magazine tests. I think that dealer recommendations and anecdotal reports from users are interesting but of limited value in comparing different tyres. The tests by various magazines (and the German AA) are at least objective, though still open to interpretation -- so this is just my take on them.
The Goodyear GS-D3 does indeed have the most impressive test results, especially taking price into account, but unfortunately it is not available in 15" (edit: actually there are a couple -- see below). The Michelin doesn't come in this size either. In fact, there are not many performance tyres available for 15" wheels, even in other widths.
I ended up getting the Direzzas, which come out pretty well in tests, so I'm disappointed to hear that you are unhappy with the wear. The tyre dealers I spoke to seemed to think that any tyres in this class are likely to wear more quickly than non-performance tyres. So far I am very pleased with them.
The Toyo T1-R is available in 205/55R15 and did well in Wheels magazine's 2005 test -- performing a bit better than the Direzza. They are, however, about $40-60 per tyre more expensive. Their predecessor, the T1-S, got some good results in one test ('EVO' '02) and some not quite so good results in others (e.g. 'Motor' '03). In Autocar's 2003 test, they tested a second set as a control and got such dramatically different figures that they disqualified them from the comparison -- so consistency may be an issue. FWIW the T1-S also seems to have a reputation for wearing out quickly. On the other hand, the T1-R is one of the newest tyres available in this size and, according to Toyo, is a big improvement. Personally I'd probably have gone for these if they weren't more expensive than the Dunlops.
Other tyres available in this size:
BF Goodrich G-Force Sport: Like the Direzza, a fairly new design which performs as well, if not better, in tests and is about the same price. I was going to get these until I got a good deal on some near-new Direzzas.
Goodyear NCT5: The same price as the Direzza but a couple of dealers suggested that they would wear and ride better. (The Direzzas seem to ride better than my previous non-performance tyres.) Goodyear do not classify these as performance tyres but in Wheels magazine's 2004 test they did quite well. In fact, they rated about the same as Bridgestone's Grid 3 performance tyre -- but not quite as well as the Direzza or G-Force. The German AA (actually ADAC) marked them down for their aquaplaning performance. The other magazines don't test this so it's hard to compare, but it could be that they suffer for not being directional.
Bridgestone Potenza Grid 3: These are popular recommendations on this list and did well in the tests -- in particular they seem very well balanced. However, since they performed only as well as the NCT5 yet cost as much as the Toyos, I'd only consider them if you got a very good deal.
Pirelli 6000: Another tyre that is not specifically touted as a performance tyre. I don't have any test of it but I expect that it is in the same class as the NCT5 or Grid 3. In this size, however, it is a bit cheaper - which surprised me.
Hankook Ventus K102: Hankook's K104 seems to be a real performance bargain but unfortunately doesn't come in this size. The K102 has okay performance figures, especially braking, but wasn't particularly liked by the 'Motor' magazine tester. This was in comparison to some pretty good tyres though. FWIW they really like them over on the Falcon Turbo newsgroup
My previous tyres were lower rated Hankooks and they really weren't bad, so if you're on a budget I expect these are fine -- you can get them for about $100 a tyre. (Note that the Kingstar K106 is a lower rated tyre.)
I didn't check whether Yokohama's V-102A or C.Drive are available in this size. In Wheels's '05 test the former performed about as well as the Toyo (it did even better in the '04 test!) and the latter about as well as the Grid 3, but I would guess that they are more expensive. Falken and Kumho also make good tyres but seem to have priced themselves out of this market.
Anyway, I hope this is helpful. I dare say someone will charge that this is all rubbish since I got it out of magazines and everyone knows that X is crap and Y is the best, but it is very difficult to get good consumer information on this issue. The tests I have mentioned have at least attempted to make objective comparisons.
As for dealers, if price is important to you it is worth ringing around. This is a pain but prices vary considerably. In Wellington I was impressed with Tony's Tyres, who really do seem serious about undercutting the opposition -- and they have free puncture repair. Of course, you first have to collect quotes from the opposition.
)
