Help Oak European V American White Oak

I am not sure what the pros & cons are of the two species so would like some comments from our knowledgable team !

The use will be an open plan staircase and have been looking at material for the strings, most suppliers only have 32mm thick, finished, I would prefer it to be 40/45mm and the only one I can find who supplies this is in American White Oak. The width is 250mm [10"] and 3.6m long

I have made two stairways in the past but well spaced apart, one for my house about 45 years ago & another for my sons first house about 25 years ago, they were in Iroko & Pitch Pine respectively.

Thanks in advance for any info or advice.
John