Very good value I thought.
But you need an extra long screw bit to use with them (and probably an extra long drill bit) then you can tighten after fitting the next panel in place). Get some panel samples off Savoy as well. You can use these to hold the clips in place prior to drilling and/or screwing into place. This speeds things up considerably otherwise you are constantly putting down and picking back up the drill.
Nobody seems to sell the extra long drill/screw bits which are essential. So you have to go online. Come on Savoy.