I think that they would be interested in us, just like we are interested in microorganisms in comets. The evolutionary difference might be so large that there is no feedback effect, that we cannot recognize them or if we recognize them they might be incomprehensible and we perceive them like insects perceive us.
But somehow I doubt that even highly-evolved beings could do anything more tricky but wormholes, bending space and so on. It's not like Einsteinian physics totally invalidated Newtonian physics and contemporary biology merely refines Darwin, so science seems to have more in common with building pyramids than with "creative destruction".
That's why I think that the speed of light limit is fairly solid.
But that's jsut my personal, fairly conservative view and "there are more things in heaven and earth ...".
