I've used both Philips and Sony sets in my work, although not the models you mention. One can't categorically state "Sony sets are superior" or "Philips reproduce colour better" as I've seen great and less than great sets from both manufacturers. What I can state is that at the top end of their respective product ranges, Sony and Philips have some remarkable sets. There is no substitute for a side by side comparison, which is what I would suggest you do. Take along your favourite software as a reference so that you can compare the two sets at the same time. Areas which I find critical are deep blacks and correct reproduction of flesh tones. However, bear in mind that TVs in shop displays are rarely if ever callibrated correctly, some even default to over the top vivid "shop display" mode that really show off stuff like The Simpsons and animation stuff, designed to catch the shopper's eye.
At least you seem to have settled on LCD instead of plama, so that's one hurdle you have crossed. I do think that the latest generation of LCD is the dog's danglies when it comes to colour accuracy, although all bets are off when the LaserVue sets from Mitsubishi arrive on your shores after the Summer hopefully, with sets boasting a colour palette twice that of today's best sets and using a quarter of the power used to run the average plasma model..
Super bright 73" monitor anyone?
To sum up, only you can decide what the best picture is for your eyes and viewing material and I've said it before, visiting your friendly, knowlegable specialist dealer (do they still exist in the UK?) who is willing to take the time to advise you and let you play around is worth gold. Sure, you pay a few pounds more on the ticket price but let's face it, it's a fairly high bracket purchase and one you will have to live with for several years, so it's worth it for peace of mind.
Buying mail order is great until someting goes wrong then the shipping charges soon make up the small saving you made.
But you can certainly compile an audition list of sets by talking to some of the very clever people who lurk within these very pages!