I have no experience with pricing of the different Powercore versions, so I don’t know if this is a good price. Unless you will need the three extra plugins, you should certainly be able to find the Element card at a cheaper price. Also consider that if you buy a PCI mkII, I believe some of these extra plugins are included in the base package.
I have only tried the Powercore FW with Podium, but the Element card should behave no differently. Be aware that all the plugins will introduce latency of an additional buffer, due to the fact that the audio must be queued for transmission over FireWire. Podium will compensate for the latency.