Everybody has got hung up on speed of sheels, the faster the better..... maybe but No....
If fast shells are best why do winchester load their trap loads to 1250, because they hold patterns better and dont kick.....
Probably the nicest shell I ever shot was a winchester load done for Landrover, 28g (twas before 24g), in boxes of 100, soft as silk, pattern like nothing else, balls of soot at any distance and as slow as a Lada on an uphill climb running on 2 cyls... Price.. cant remember, not in Biakal or S&B territory but cheaper than trap 100's.
If I lived on mainland Europe I would be going into Frankonia for these
http://www.frankonia.fr/12-70%2C+Super+Trap+(24gr-2%2C4mm)/Sellier+%2B+Bellot/Apercu.html?Numero_d_article=107475&lastSelected=f_n_schrotgewicht_in_g&f_n_schrotgewicht_in_g=12%2424&navCategoryId=6557