As a quick price comparison, the second box is about 105 cubit foot, which costs £769.33 for the box, picking it up, shipping it, and delivering it the other side. Do they pack it for that though? If so its not that bad I guess - but for a comparison we have had a quote for 160 cubic foot for £898, them packing everything etc, with Marine Insurance of 1.5% of total value of stuff, so only another £130 for another 55 cubic footage.
The other good thing about them packing it as well is they should put the things that will need inspecting in one place apparently, which speeds up AQIS inspection, which means it costs you less - if you've packed it yourself apparently they are more thorough in their search through things so its going to take longer and cost more :(
But as I say, if you know you only have boxes (2/3 of our move is a huge rocking horse and some oil paintings that are also HUGE), they may be good :)