No. It is never a good idea to have a sofa against a lounge radiator or any other sort of designer radiator.
Sofas, or other forms of large furniture, can block heat from travelling easily around the room, and could be damaged over time as a result of close-up heat exposure.
Meanwhile, for an insight into some of the finest lounge radiators available, take a look at our Advice Centre blog, The Best Designer Radiators For Your Living Room.