You can get some limited 5% deals but they are limited to only a few thousand pounds and there are strings attached- eg pay in £1000 a month and do a full current account switch
The abswer still depends on several factors such as how much you have to invest, how long you can tie your money up for and whether you can comply with other conditions
Paragon looks okay but even their best rate which requires having money tied up for 5 years is 'only' 3.1% so it can't beat the suggested 4%- however I am not aware of any Prudential account/bond that guarantees 4%.