The article will present and discuss the issues found in Source for Production of Ion of Deuterium Extracted from RF plasma (SPIDER) experiment with the operation of the radio frequency (RF) generators based on self-excited tetrode oscillators and the advantages expected from their replacement with RF solid-state amplifiers. The assessment of the solution based on new solid-state amplifiers for both SPIDER and Megavolt ITER Injector and Concept Advancement (MITICA) experiments operating in Padua, Italy, in the Neutral Beam Test Facility, will be described, outlining the main design challenges and open points.