Hey Joe,
I'll answer excluding 1890 PL Boston as that would carry a healthy premium (but no NM examples known)
As you well know, Brouthers has three poses with Detroit in 1887, two of which were re-issued with Detroit in 1888. The same two poses would be re-issued in 1889 with Boston.
The two 1889 Boston poses are quite common, ~equal to the aggregate of the three 1887 Detroits while the 1888 re-issues are quite rare. The 1889 Boston cards are often of worse photo quality, however, if photo quality and all else were equal I'd expect them to sell for ~same. If it were a lower grade example maybe slight advantage for Detroit as there are currently at least 5 collectors that seem to pursue this OJ team
