I've thought this before about these mags. Have just seen the one for building a replica of Nelson's ship Victory.
It's £5.99 per mag, and you buy over 100 of them to get the full kit to build the ship.
That's over £700 for what looks on screen to be a pretty basic model, with little detail.
I am sure that for just a fraction of this outlay you can get a much more realistic kit to build, that looks better.
They are really taking the P*.