Update

I've had the Ferline tomato and the 2 courgettes out for a while now.

All are still alive. The Ferline isn't anywhere near as big as the others that I move in and out of the GH.

The weather has been hot and cold, but no really cold nights and no frost, even so they have all been well covered at night.

The courgettes aren't as big as the ones still in pots, but one of them looks very healthy, the other looks like it may be growing into health.

I'm still not convinced by the whole, putting them out early thing.

Later on in the year, I will know better.

Hopefully after a few cold days that are coming (forecast -2 or -3 a couple of nights) it looks like it should get better and everything can go out.

edit
Flippin heck! It's like the middle of winter out there atm, icy strong winds blowing through.
Just nipped out and covered everything up, roll on summer!