What a load of shit. Planet x are a bike company (what the fuck else do they make or sell?!).
They make great bikes for reasonable money - which people have ridden to national championship wins on the track, road and TT's - there is absolutely NOTHING wrong with them.
Their assembly can be shockingly bad. A chap came to my old shop with his brand carbon machine complaining about the front shifting. The clearance between the (23c) tyre and the seat tube was so small the tyre was rubbing against the front derailleur clamp when it was set-up properly. Finding another, thinner clamp being obviously time-consuming the mechanic decided to rotate the clamp a bit, messing-up the shifting in the mean-time. But hey, at least it was not rubbing. That's the sort of corners they take.