Yeah, well i've just had mine on the rollers recently. It's managed 175bhp @ the flywheel. Speaking to the people who run the rollers and they have said, it's quite common for Altezzas to do this. All the ones they have had in have under produced. Mine being the most powerful one they have had in, the rest managing 150 - 170 bhp.
I think i might have to get an Apexi ECU next