I guess it really depends on what YOU want. Do you want the cool deep sound or is performance your main objective? Check the throttle response in those vids between the 1203 and the 1125.
I had an 01 X1 Lightning( had a few different exhausts on it)and that thing sounded wicked,pissed off,thumpy and badass.
I just sold that and got a 1125CR. The 1125 does not sound anything like the 1203...and never will.I have the stock exhaust and I'm doing some research now because I dont like the stock exhaust at all(looks,weight,and where it discharges),but sound is not my only reason. I do have to say its pretty f'n quiet til bout 7000rpm-then she howls like a werewolf.
just my 2 cents.