In Europe by far most popular 690 is 690 Supermoto/SMC/SMC-R.
Duke 690 - seen few in Germany and Italy, not sure about other countries but not so much as 690 supermotards...
We have (mostly) different type of roads and conditions. Twisties, narrow, densely built towns etc. dictates.
In my honest personal opinion over here suspension and brakes matter more than motor sheer power. Tractability, flexibility of engine is important - but not just size and bhp.On latest trip we made with many friends in 1 group we had lot of bikes of totally different types. From top of my had it was...Caponord, SMT990, Futura, BMW R100R, Tuareg 600, my Tiger 800, FJR1300, VFR800, Bandit 600, Tenere 660 (new), R1200GS - all were separated "automatically" into subgroups only by riders ability or desire to ride fast, very fast, regularly, slow, very slow and bikes had no place in this division and we always met alltogether few times a day and arrived to accomodations in the evening at approximately same time. Because it was all twisties and narow roads.