I'm looking at buying either wheat bags or hot water bottles for beds come winter.
Does anyone know which is more than efficient? We have a 900w microwave and a standard kettle. We'd need four of either.
This thread is fairly old now so some of the suggestions may be out of date, but if you’ve landed here looking for quality hot water bottles, we’ve recently updated our best hot water bottle page with lots of great options, as rated by Mumsnet users. We also have a kids’ hot water bottle guide too for something more suitable for little ones. We hope you find them useful. 
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