I have a number of G-Tech drives that are quad interface and work very well with FCP. For editing I use the FW800 interface on the MacBook Pro and the e-SATA interface on the desktop system. The FW400 and USB connections work fine for transferring files as well. Very rugged build quality and they come in a variety of sizes. The cost of these continues to drop and I think they are a "very good bang for the buck". I generally buy them MacMall as they always have stock and the best pricing.
Depending on your compression level you might want to look at a raid drive that can transfer files through an e-sata card for your MBP. Firewire 800 works fine with compressed video but if you're going to use uncompressed, I would recommend something faster than FW 800. When you start to run multiple layers of video, you can have problems at playback on FW 800 and uncompressed SD video.