Ottawa is a relatively small city with some nice architecture, and is quite photogenic with its river, waterfalls, canals, public parks and gardens. Let me know if you ever come to visit.
Regarding the 43 mm for the Mamiya 7, it would interesting, but somewhat unfair to compare it to the Pentax 45 mm, because the Mamiya has the advantage of being of symmetrical design instead of being a retrofocus lens; it also only focus down to 1 meter instead of 37 cm. Moreover, the Mamiya 7 produces no vibration being a rangefinder with the shutter in the lens.
The Mamiya has also very good flare resistance, and as Stuart mentioned, it has virtually no distortion.
The only problem I've found was composition: one has to use an external finder which gives an approximate view and has some distortion. I've often ended up with unlevelled horizons when used hand-held.