newbie concerns: FCE abilities

Hi, I'm migrating from PC to MAC (new 27" iMac), and I'm involved in created abstract art/music videos with prosumer level equipment. I'm wondering if Final Cut Express HD will suit my needs.

I doubt whether I will need the extreme "pro" level of Final Cut Pro Studio. At most I "layer" video track to a max of about 4 tracks + titles, and layer sound - again - using about 4 stereo tracks max. What I utilize a lot in "layering" video is the filters or "mattes" such as "difference" or "luminance" that allow for key-framing these effects over time along the duration of a clip.

Will FCE HD allow for this?

I also use slow motion a lot. In previous apps (mostly Ulead Media Studio), I was able to slow down a clip to any percentage degree I chose, which was very convenient. Does FCE HD have this flexibility?

Also, if any of you have experience with Sony's AVCHD file-types, and their ease-of-use in FCE, would be great to know. Currently iMovie on my new iMac immediately loads AVCHD's from my camera, and converts them on the fly. Wondering if FCE will also do this?

One final question is regarding FCE's flexibility in mixing different file-types. One of the joys of Ulead's product, was that it would seamlessly integrate almost any movie file-type and almost any audio file-type. I understand that Mac's will likely be limited that way, but as long as FCE can convert to a useable type, that would be great.

thanks for any input on the above concerns ...