OK, the gear4music guy didn't get back to me in 2 weeks, so I went out and tested some 2x12s (Brunetti, Fuchs, Custom Audio, Matchless, T.Rex, Heritage).
The Heritage won the race. It's got a Vin30 and a G12H30 and kinda Thiele openings in the front, it sounds very full and open, just the right balance for 450€. It's a cab of the new amp range from Heritage, who usually build "the better Gibsons".
I have to say the Brunetti was very nice too. 2x Vin30, with very much oomph and crisp highs.
Very happy with my choice. Also the versatility of two different speakers is a useful feature. On the next gig, I'll place the mic quickly in front of either speaker and ask the sound eng which one instantly gives the better sound.
One thing: I haven't been aware of how much influence a cab actually has on the quality of your sound. I always thought the right amp and speakers will do. But I realised that the cab design and quality make a HUGE difference!