Sony W Series 37" for sub £400
Found this instore. Not sure if it is nationwide but the store manager confirmed stock.
This is £100 less than the Argos deal for the 37W5710 (which has the same screen but aesthetically slightly different).
thanks to thehitman - It should have a standard Sony warranty that is currently 3 years until the end of this month
updated on 23/11/2011:
Recently, my tv bought on this deal died and I had to dig down the information regarding the 3-years warranty. The only thing you need to claim 3-years warranty from the date of purchase is the original purchase receipt. Thanks to Yiddo4life (post 425) Full details can be found at the link:http://campaign.odw.sony-europe.com/tvme/h086/pdf/BRAVIA_en_GB_Trade-in_Ts_Cs_&_3yr_Guarantee_info.pdf
I called on 03304402060 to claim the warranty. The information they need is the model number and the date of purchase.
I hope this information helps for somebody else. Cheers.