Two lasts that we don't see that often: Phila (on the right) vs. Robert in dark brown suede on the left. Both are size 9.5.
Phila looks and feels slightly wider. Fun fact, however, is that both lasts are 4 1/8" on the widest part of the sole. The sole shape is actually different though.
The Phila last has a clearly lower instep and arch, as seen most clearly on the last picture.
edit: Phila also has a slightly wider heel and midfoot.