Brin,
I know exactly what you're after, as its what I wanted as well. I was not interested in woofers, subwoofers, amps etc etc.
IMHO, thats for kiddies, and just serves to attract the boys in blue (and thieves) and to make you go deaf.
RMS = in very very simple terms, it is a mathematical formula that gives you the average power (this is a really simple explanation). This the value you ALWAYS need to look at, when looking at audio output.
Retailers always highlight the 'bigger' PMPO (peak music power output) value, as it makes the speakers (or whatever unit it is) sound better than it actually is.
The speakers you mention are rated 90w RMS. They should be more than adequate. It all depends on what headunit you are using, and its output.
A good rule of thumb you can use - whatever the RMS output of your headunit, install speakers that are at least the same output plus 20%.
The standard Fiat unit, if I remember correctly, is rated at 25w RMS.
The only thing you need to worry about, is the depth of these speakers. The original speakers are a bit shallow, but that can also be adapted with some patience. I think 44mm should be ok - can't remember.
Best way to shop, is to take one of the original speakers and measure it up.
p.s: I made a mistake regarding the size of the parcelshelf speakers. They are 100mm (not 80mm), and with an adapter you can fit 130mm.
what is RMS??
the ones im looking at:
http://caraudiosecurity.com/shop/product/products_id/6411.html
are 35w rated input and 200w peak input, which is the magic number?? 35 or 200?? lol
and is 44mm depth too deep or will it be ok??
thanks