It was a bit of a nightmare getting any decent reviews or comparisons for entry-level home cinema systems.
Most quality magazines/sites were only interested in systems over the £400 mark - well out of my budget!
Most audiophile reviews turned their nose up at budget stuff and/or were unfair;
one respected magazine compared the Sony HT-P1000 (a HT-SL5 + a DVD player package) with other packages that started at nearly £200 more going up to over £1200.
Strangely it didn't compare very well!
So I had to do a lot of detective work by using more expensive equipment reviews to get a general feel & forum sites especially www.avforums.com.
I eventually took the plunge and choose the Sony HT-SL5 for several reasons.

Firstly it has two optical inputs which I needed as I have optical out on my Sony satellite decoder and my Xbox has the advanced scart (adding opt. out.)

Secondly it has Dolby Prologic II which I was hearing very good things about after my search on the web.

Finally the price was in my budget (just!)

I also pushed out the boat and bought two pairs of Alphason SS-20 stands to hold the speakers.

After the initial 2-3 hours of sorting out cables and connecting everything properly I finally got round to setting up the system. The manual was good and explained how to set most things how they should be (speaker distance for delay etc.)
I must say at this point that I was upgrading from a integrated Prologic system on a TV so a separate home cinema system should sound a lot better.

So the moment of truth - Monsters Inc in the XBox and away...
I must say that after the THX 'show off' at the beginning of the DVD I was sold but when my sofa vibrated during the 'chase' scene at the close of Monsters Inc I was convinced every penny was well spent!

I can't give flowing prose about mid-range, dynamics or sound-fields just an opinion.
This system has improved everything about my TV/film/gaming experience.
5.1 DVD's are like being at the cinema without the muscle cramp or annoying kids.
Dolby Prologic II improves TV broadcasts & videos.
Halo on the Xbox in 5.1 is what the Xbox was made for!

I'm sure if I spent a few hundred pounds more the sound would better but I didn't have any more money - a great sound for a good price!