Well, you don't need a fast starship to get to Alpha Centauri.
Spoken like a true sf fan! The Centauri system is thousands of years away, at our current top speed.
No, spoken like someone participating in an ongoing conversation whose topic is the fictional
Star Trek universe in which warp drive exists. By the parameters of
that universe, by the parameters established in
T'Girl's post which I was responding to, a "fast starship" is one with warp capability beyond what humanity possessed between the
Phoenix's inaugural flight in 2063 and the launch of
Enterprise in 2151. I was saying that the "slow" warp technology possessed by humanity in its first nine decades as a warp-capable civilization was more than adequate to establish a colonial presence on Alpha Centauri without needing to rely on other civilizations' superior warp capability.
Our
current technology in real life is an entirely separate conversation from the one underway in this thread. So I don't know why you'd think it was relevant here.