You guys could do us (and yourself) a huge favour if you'd write the correct net. weight for each product into the shop listings.
Because sometimes not only size matters but also weight.
For some of your products their is no weight in the data, at least once (see RD 8) it is utterly wrong and for others it is including the case. So right now one can't trust those figures at all.
Bring a scale to Portugal :))