TERRIBLE. AVOID.
I placed an order for a next day delivery. The flowers are still yet to arrive 2 days later (as I write this). The customer service politely reminded me i clicked the purchase confirmation button that effectively says 'WE WILL NOT GUARANTEE TO DELIVER YOUR FLOWERS WHEN YOU'VE REQUESTED BUT WE'RE GOING TO TAKE YOUR MONEY ANYWAY' and offered me a 20% discount on a future order (on what are significantly overpriced flowers anyway).
So do yourself a favor and AVOID AVOID AVOID.
If you need a flower delivery for the UK. I recommend Serenata.