Of all the people on this board, I probably respect Fred the most, so I am very guarded with what I say here.
I have had such great luck with the E3 70 rear tire fixing so many things that I think it is worth a shot for most riders.
1. It lowers the engine RPM at a given speed by 6.8%
2. It picks the bike up about 3/4 inch in the back, and when coupled with stiffer front springs, makes a significant difference in ground clearance.
3. The speedo is dead on at 65 mph, and very close from 50 mph up. The odometer is about 1.2% slow.
4. I reluctantly changed tires last Friday with considerable tread remaining on the rear tire and some on the front, because it was time for service and approching time for some trips and I did not want to start out with tires that had 23,000 miles on them. However, I have never had that kind of tire service before, and I am sure they would have gone 25,000 miles, real miles. Remember that I never ride without the Tailwind on the back.
I will admit that the tires are noiser that the D250s or Bridgestones. I am like several others in our group that use the E3 70 tires, I will never go back. If I was aggressive and did Deal's gap every day, I might feel differently, but it really fits my riding style to a tee.
Relative to the brake shudder. I had it often on the 01 bike and have only had a small hint of it once on this bike. The only change that is obvious on the 04 and later is the shield on the inboard side of the right hand muffler. I never used a full size tire on the back of the 01 either. The brake shudder may still be there if I were to dog the brakes hard, but it is definitely far better than the earlier bike.
I agree with all of Fred's comments, tempered slightly with those above.
Relative to the lifters, it appears to me that the lifters are a lifetime deal.
So far, I have not had a fender problem in 107,000 miles, but I would like a longer aft half of the fender.
I do have an annoyance, and that is the alternator drives later in life noise. Maybe the 06 is better. Mine rattles far too much at lower rpms.
I would love to have the bike as quiet as the 1500 is, mechanically.