Material grades are always evolving.
Corrugated paper names have always been classified by their grammage (g/m2).
Historically, these were always classed as 125, 150, 200 and 300 for conventional material types.
Over time, the manufacturing processes used to make the paper have improved, with meaning that the name is only now used as an easy identifier for the type of performance you can expect from paper weight.
As an example, a 150g/m2 paper now actually weighs between 130-140g/m2, but is classed to perform like a 150.
Like with paper weights, printing quality, particularly in Flexographic printing has moved on considerably in the last few years.
Whilst most modern manufacturers will have the most advanced machinery available, a lot of older machines are still in service which don't offer the same printing resolution without a costly upgrade.
But the general rule of thumb is that for the best print coverage, you should really use the heavier weight papers on the outside of your packaging.
Brown Kraft, over 150g/m2 would be preferred, especially for lots of block and flood printing, but printing to brown can result in vast differential in colour reference. Printing on White Kraft or Test (Recycled) will often produce the best result.
Thats not to say you cannot print a high quality print on a 125 weight paper, but you do increase the chance of seeing flute shadow through the liner, and this paper weight does absorb a lot of the ink, sometimes producing a patchy poor quality print.
Many companies pick double wall boxes because they think it offers superior protection to single wall.
Most of the time, this would be correct.
Most companies will stack 90 DW boxes per stack to ensure pallets can be double stacked on their vehicles.
B flute and the newer "R" flute profiles can be stacked at 180-210 per stack on a pallet.
When comparing the performance of a heavy weight single wall to a light double wall, there is practically little difference, and it will be small price saving as well like for like.
In a word, no.
Whilst the sample will have exactly the same internal dimensions, and assemble exactly the same, there will be subtle differences.
The main noticeable differences will be the thickness of the material and the resistance of the panel creases.
When a sample is made on a sample making table, the only pressure applied is to the creases and scores, and only then can the machine penetrate so far into the material.
On a production run, the creasing tools on machines and cutting tools apply several tonnes of pressure at a time, breaking the natural resistance of the board in those areas to make it fold better. Also, with many drive rollers pushing the material through the machine, this can crush the board slightly.