I have scooped some absolute bargains in the Next Sale, but always online.
A couple of years ago, on Christmas Eve, I managed to kit out DD1's new bedroom - wardrobe, chest, shelves, bedding etc. for half price, really good quality stuff.
All my running kit (Nike) came from the Next sale, half price, and way cheaper than even the discount sports shops. DS1 is a fan of branded shoes, such as DCs, and we always pick them up cheaply too. Ditto trainers for school.
This week I had a VIP online slot on Wednesday, one of the really early ones, and bought loads - a dress and a pair of trousers that I nearly bought a few weeks ago, but thought I couldn't justify the price; also some new jeans and teeshirts for the DCs, a gorgeous pair of curtains, a few accessories to put in the present box......I could go on.
I think you have to be selective regarding the women's clothes (there was a lot of drapy dippy-hemmed putty-coloured stuff in there this summer), but they do really nice workwear, little cotton shirts, great trousers, and I love the fact that it can all be done online.
And it's a PROPER sale; none of this "10% off" rubbish.
I would never get out of bed at 5am for it, though!