Hi Pete
I've been on a couple of Birdfinders trips - Finland for the Owls (as you "need" a guide to see them all, especially in a short timeframe, a long weekend), and Israel this autumn (as a friend was also going, and didn't want to self-guide, and I quite fancied a lazy trip without the need for driving!). They were both really good trips, well-organised, with excellent leaders. I'm also going with them to the Urals in June, as the exploratory nature of the trip appealed, and as I have no time to organise something like that myself, nor a desire to go on my own. However, to be honest I'd never contemplate a trip to Scilly with an organised tour; it has a place for certain punters of course, but you can go there on your own and never "be alone" (whether or not that's a good thing I'm not entirely sure). There's also no need to worry about feeling like a novice surrounded by experts; there were plenty of beginners around every time I went there! You're unlikely to miss out on news of a rare bird, as if you are anywhere near the town when a rarity turns up, you'll hear the stampede....