hmmm
r to the s is quite different in terms of ducati but compared to the rr its a million miles away.
The 748r is a triuy amazing, awesome handling and performing bike but its not necessarily the most user friendly depending on what you want your bike for. If you want a track tool you can't beat it. If you want a stunning road bike that you have to put the effort into its also amazing. Its not necessaily a great bike for someone who wants to do long rides without constant gear changing or who just wants a leisurely ride.
If you want the lazy option with great performance and reliability and less lumpy go for the 998. If you want something closer in feel to the 748r but with a bit more grunt for lazy days go for the 996.
But, the 748r does come with some great extras that you will only start to find on 996 sps/r or 998 s (i may have those wrong tho
) such as Ohlins front and rear, smooth side panels. 4 pot brembo
Compared to the rr they are all gonna be very very diffferent and the 998 probably has the closest in terms of power, reliability, ease of riding but its posssibly not as 'involving' as the 748r