Ppro is a great application but fcp has its advantages. In my experience FCP is more stable than premiere. Especially if you are working on larger projects.
Another poster addressed final cut audio editing tools, as far as these are concerned, in premiere you end up using more keystrokes/mouse clicks to keyframe audio. I have also had issues using premiere/soundbooth audio filters. When rendered they can cause distortion. Also while editing HDV there is audio dropout during playback even when rendered. When it comes right down to nuts and bolts though both programs accomplish the same ends and premiere can easily be customized with fcp keystrokes. If you are on a tight budget then cs3/4 is the way to go.
Why not upgrade to cs3 or cs4 for photoshop and after effects and continue using fcp as your nle?