This any good

depends what you want it for?

5.1 is always good enough.

them extra 2 speakers are pointless IMO

Depends what its for. If its for your carputer which I believe it is. I would invest in a slightly better one such as a Basic Sound Blaster even a Audigy if your buget stretches. These cards a better shielded for interfearence and have much better DSP (Digital Signal processing) which enchances the audio as well as some configurable effect with EQ, EAX .

I think the fact that the brand is called Sweex tells you that it's probably crap.

Sorry the above product was just to start the discussion.
Yes it is for the Carputer and i was told that a 7.1 sound card has more outputs so i can use more RCA cables with a higher signal as for some reason i dont really want to use a Headphone socket to send a signal to about £2000 worth of audio equipt and still rising.
This has been the most frustrating part of the whole process so do i use a Top notch sound card (I have an unlimited budget within reason) Or keep the Hu and get a Line Driver.
Also does anybody know weather i would benefit from a household digi converter cos i know a guy who has a really good one and he loves well built systems so im sure he would sell it too me if i told him why i need it.

the output(s) you need will depend on what you're sending the signal to. i cant think of any situation when you would need more than 3 outputs; front (stereo), rear (stereo) and sub (mono). 7.1 has 7 mono speaker outputs and 1 mono sub output, so you'd only be using 4.1, leaving 3 unused.

ATM I need 4 sets of preouts 3 for one amp and one for the other and i may be putting in another amp soon. So i want to send as high quality signal to each amp obviously for the best sound output. At the moment i am making do with the two 3v from the HU and then using the signal out from my Mono amp.

The problem is getting them all working. Computer sound cards hardly have the ability to upmix 2 channel audio to 5 channels, and most try and simulate surround sound.

The Creative sound card I use could have a potential 2 x 3.5mm jacks, and that equates to 2 pre-outs. Connectors dont really matter if your only using an analogue signal.

I don't think you'll be able to get a PC soundcard that has 4 ways of outputting the same stereo signal at once.