Are the products specified weights the real weights?
No. The item weights have been adjusted for purposes of calculation of shipping costs! If actual product weights are important, they are given in the article text. With F-connectors and adapters I consider this but for Sinnfrei.
Walking except DHL and antennas also DPD other shipping methods?
Yes of course. If other shipping methods are desired, enter please see the comments field. I use DHL only because a parcel box is close to me. DPD is the cheapest supplier for large packages.