Thanks dtw, think I am probably looking for something with a more 'conventional' chilli flavour, if that makes sense! But I'll keep Aji Crystal in mind for when space isn't as limited and I have room to experiment.
Saddad, thanks! No greenhouse :( so don't think I could risk it in case the whole lot failed - if we get another "summer" like this one, that's entirely likely!
Weedgrower, what's good about each of them?
C'mon chilli-heads! There must be a killerdiller chilli out there just waiting for a place on my plot!