I am going to review the trilogy here and not just the first book. Aldiss said that the trilogy has extreme structural flaws and this is certainly the case. It is not really a trilogy at all. It is a set of interconnected short stories with the natural break one third of the way into book 2. Asimov can't write characters at all and does not really do action, so that it is mostly a bunch of ciphers sitting around talking. However, the ideas are interesting and there is something about it that gives the sense of an epic and the impression of a real galactic empire. Asimov is clearly drawing from Roman history and the dark ages and looking forward to the renaissance.
Asimov's work is extremely readable, but in the end there is no way to look at the foundation trilogy as anything other than overrated. It has its merits, but there is plenty of science fiction that is better.