525i 24v are 193hp but the power is quite high up the rev range and so is the torque.535i's are 12v and 211hp,but have a lot more torque low down.
all sports had lsd's as far as i am aware,525 or 535.no other 5 series had a sport option.not sure on fuel economy,my 540 has avaraged 19mpg over the last 12 months.
the engines are bomb proof.the 525i engine is the one that gets turbo charged a lot in sweden and norway.they make 400-500hp with just a piston change .
bryan