The 'Live' magazine/supplement in the Mail on Sunday (16th May) had a review of various barbies. Not a scientific review by any measure, but it does provide some comparisons.
Out of 15 models listed/reviewed, only two acheived a 5-star rating ...
one was a 'Swiss Grill' costing £1300 from Harrods (!
) - but it's gas-powered, so doesn't really count; and the other was the Weber Compact Kettle costing £100 from Lakeland.