Earth-like? I'd believe it when they get there. Here's the travel time:

-Current rocket technology (if a large enough one could be built): 120,000mph.
25,000 years to get there.

-Project Orion 10,000 ton class ship: 80% speed of light peak speed.
14 years.

http://www.cnn.com/videos/world/2016...d-orig-nws.cnn