Logging co-pilot time in a single-pilot aeroplane is more legit in most cases than Qlink's ICUS program. Unless most of the line captains at Qlink are training captains, and the 'FO' is sitting in the left hand seat, I can't understand how they get away with logging so much ICUS. I don't care what the ops manual says, it is a scam and I can't believe CASA tolerates it.
Back to co-pilot time, once came across a lady who had a GFPT and did a fair bit of private flying with friends in everything from drifters to Bonanzas to twins. She later did her PPL and the flying school starting checking her log book to total her hours. They were amazed to find she'd logged a few hundred hours of co-pilot time on all of these private flights, and she was dirty they now wouldn't contribute to her total time. Who cares that she wasn't endorsed on the twins, didn't know how to fly the other aeroplanes, or in many cases hadn't touched the controls. The fact she was allowed by the pilot to fly from the right hand seat (with a GFPT, many many miles from the flying school) was also dodgy.