Car N00b Looking For First Car Options

[xyxvv]

Hi all, I'm looking at the Yaris Sedan and 5 door as my potential first car. A few things I'd like to know before heading off to the dealearship since I've been poking around the build your own on Toyota's site. The sedan at least feels roomy enough to me and the city mileage looks great for the price after looking a all other cars in the price range.

I'd like to know, with the 5 door how much trunk space do you get? The local dealerships don't have any of them in stock yet, only base model sedans. The fold down rear seat is also a big plus, it looks like only the sedan has it with "Option B" on Toyota's site though.

The other things are the optional performance parts, is it worth it to get the upgraded clutch, the rear sway bar, the performance air filter and the Sport muffler? it does seem that the clutch at least would be worthwhile, but reading a little about how the sway bar works worries me a little since I'd still consider myself a beginner as far as driving skill. That and the site doesn't say what the sport muffler does for performance aside from the unimportant sounding "enhanced sound". I'm more or less wondering if the better air filter and muffler will aid in increasing mileage or add an extra Hp or 2, since I live in Wisconsin, dealing with snow is a pretty big concern, which is why I don't care much about the spring lowering or spoilers, getting down poorly plowed roads is something to care about though.

An help will be much appreciated.