[91LX2Bfast]

I think most people would rather have had Ford keep using the 5.0L, but they didn't, so we have to make do with what we have. Every Mustang since '96 has come with a 4.6, so thats why people are modifying the motor. Not everybody wants to buy a 8+ year old car just to have the 5.0L in it.
The only years that the 4.6L 2V was really a weak motor was 96-98. In '99 it got new heads and intake, and was bumped to 260hp, and could run faster then the old 5.0's. The 4V has always produced great numbers, although its not enough to compete with the big 350's GM puts out.
As far as making big power, well, throughout history Ford has rarely ever built the Mustang fast the the Camaro or Firbird except for those rare few years in the late 80's and early 90's. Most people buy Mustangs for a combination of things: Style, decent power, build quality, comfort, aftermarket availbility, etc.
Yes, you are right, to really make any big numbers with the 4.6, you have to use Forced Induction. But, thats the way it is with 99% of todays motors.
So basically, people "like" the 4.6L because its the only thing you have to work with if you want a newer Mustang.