I was going for stelrad designer radiators, but the price of them was mad.
Under someone's suggestion I went for NRG radiators.
A third of the price, same design and they work perfectly.
They get hot all over very quickly and when you turn the central heating off, they stay warm for a long time.
I'm happy with them and buying through Amazon I got them next day.
Only downside was that I had to flush them before fitting because I could hear metal dust moving in them.
And for the first few days I kept on cleaning the magna filter.
Don't know if it's the same for other radiators though.