The food is a bit hit and miss at Hotel du Vin. Given it's quite expensive and a chain, I find it hard to forgive it for this.
However, the bar is well worth a visit for the cocktails. Like the restaurant, it is open to non-residents. There are all the old favourites on the cocktail menu, plus the bar staffs' original concotions. My personal favourite is the Turkish Delight, which manages to combine rose and lemon in a floaty, light, yet sophisticated, whirl of deliciousness. If it's not on the menu, ask for it. Cocktails are around £8 to £9, so not cheap. Yes, you may need to re-mortgage, but they're so good, you probably won't mind.
Look out for the chandelier made of wine glasses.