Rarely does one get to see them side by side as fruiting conditions are just different enough that they tend to pop at different times.
Even given that the L. sulphureus is rather young, and then L. cincinnatus is fully mature, you can see the striking difference in the pore surface (lower picture). The former is bright yellow where the latter is white-cream.
Furthermore, where L. sulphureus generally grows on logs in the summer and fall, L. cincinnatus generally grows at the base of a tree or up from underground roots in rosettes in the early summer and late fall (so it seems to like things a bit cooler).