PCI isn't sufficient for the /theoretical/ bandwidth of SATA, generation 1 or 2. However, the /actual/ throughput you'll get from today's drives still is less than the roughly 100 MB/s a "plain" PCI slot can handle.
Still, this one PCI bus will be pretty saturated by the SATA controller activity, so if you got a sound or TV tuner card on the same bus, don't expect things to be smooth.
Chipset integrated SATA controllers may or may not support hot plugging - that (optional) feature was part of the SATA specification before the eSATA idea appeared.