In terms of raw performance networkx.pagerank_scipy can be 4-5X faster than networkx.pagerank. For the google.txt file on my local machine.
In [4]: %%timeit
...: nx.pagerank(G, alpha=0.85, tol=1e-3, max_iter=10000000)
...:
40.1 s ± 5.19 s per loop (mean ± std. dev. of 7 runs, 1 loop each)
In [5]: %%timeit
...: nx.pagerank_scipy(G, alpha=0.85, tol=1e-3, max_iter=10000000)
...:
8.89 s ± 48.3 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)```