Dahlia visitor

Ok, I hate to admit defeat, I've been trying to identify this insect, one of six on my mums new dahlias this evening. They were feeding on pollen, (they have almost a tube like proboscis) someone suggested a wasp beetle, it does look like that but lots of other aspects don't fit, antenna and legs appear to be longer and finer for starters, unless it's a variant. Fairly sure they fly too. Any ID suggestions most welcome. I hope they aren't pests, they are quite pretty wee things. And yes, I'm still playing with the macro lens for the iPhone, it's addictive! :-D