I had a ZZR1200 from new and to be honest I didn't like it much. I traded it on a ZRX1200r which is much better.To compare I had the ZZR for five years and did 29000km on it. ZRX I have had for just over two and done 26000km.

Handles better, brakes and seating position are better also. Mid range power is better but ZZR has better topend. If you are chubby like me the ZZR may be a reach to the bars as the rear of the tank sticks into your gut. Build quality was dodgy. Painted surfaces were mismatched, and there is a design fault where the upper fairing rubs the paint off the fuel tank, exposing the metal and causing it to rust. Plastic feel to it. Headlight and dash are plastic unlike the excellent ZZR1100 which was glass. I'd be looking at a good ZZR1100D as a touring bike rather than the ZZR12. I had the 1100 and the 1200 was a disappointment after it.
The only downers regarding the ZRX as a touring bike are no centrestand, and a smaller fuel tank- 19L. IIRC the ZZR11 was 24L and the 12 23L. Panniers don't work well on the ZRX either. I had Givi panniers off my ZZR fitted to my ZRX and they caused it to understeer badly. The pipe on the ZRX is too high for full size panniers.
Regarding the ZX12R I rode one years ago and my vague recollection was that it was a bit faster than the ZZR12, and handled somewhat better. I don't think it would outhandle a ZRX. Guy I subcontract for has a ZX12r streetfighter and he reckons the handling is nowhere near as good as my ZRX. (He has ridden my ZRX a couple of times.) He reckons the longer wheelbase of the ZX contributes to the slower steering. I guess you need stability over 300km/h!
There is a tosser here who I am surprised hasn't chimed in yet to tell you how great the ZZR is and how crap the ZRX is. I guess we'll see it shortly.

2 X ZRX1200R 4 X ER6N, GT550, 1988 ZX-10, 4 X GPZ250R, 4 X GPZ900R and GPZ750R

Yeah I like Kawasakis.