They are on the narrow road from the port certainly as you describe but traffic was not a problem and noise not a feature at all. With a car there is ample parking room.
As it happens we were without car and thus the walk to Trogir was about 5 minutes (only 50 metres of which was on the road)and thus easy and convenient.
These apartments are rightly popular and even in our September visit were proving so.
An ideal base for most - perhaps those with a real difficulty walking would find the last 300metres returning from the port a little steep ..
On arrival we caught the 37 bus from outside the airport as was our wish but the family are happy and ready to collect and drop without charge - nothing too much trouble for them in fact.