Sugino 75s vs. Grand Mighty

Picked up what I thought was some 75s on eBay for 70quid (second hand, extremely good nick), but the logo looked different and it turns out they're Grand Mighty's instead.
Bit of Googling reckons they're better forged than 75's but suffer from 'deliberate flex'.

Not had a chance to ride them yet, but has anyone experienced the flex, or have any more info on them?

The 'deliberate flex' is a pro level thing. If you are not a pro, you will not notice it.

The flex is design to smooth out the very slight pedal speed variations of top kierin riders. If you are not putting out over 1800watts (and if you don't know whether you are or not, then your not) you will not notice any difference.

Good buy!