I've got 2 imposters growing.
I sowed and planted out what should have been a Black Beauty Courgette. Well, they are definitely not black! They are a mottled yellow/green and trumpet-shaped and grow very big very quickly.
The one I'm more cross about is the butternut squash which isn't remotely butternut-squash-ish. They are currently bright yellow, round and football-sized. The variety should have been Winter F1.
Both were Wilkinsons seeds so I suppose you get what you pay for. I'll take some pics next week and post to see if anyone can identify them. I'll also let Wilko's know. When I got weeds instead of horseradish, their customer service was very good and they were generous with vouchers, so fingers crossed. I'd still rather have had the butternuts though :(