Me too, I qualified for the grace period, which I'm happy about, as I would've been a bit miffed to have to fork out another £50 for an upgrade/update (even though I only paid £150 for upgrade from Studio 4).
ANYWAY, I think Retrologue is an excellent addition to Cubase, and of course so is Padshop. Only other production program I've used is Reason 5, and Thor is quality. Cubase direly needed a decent modern-quality stock synth, and I must admit, I really like the sound of Retrologue. Padshop to me is better at Pads than most of the modern 'pad' synths i've tried.
People have been comparing Retrologue to Sylenth1, but i've never tried that synth. From Sylenth's rep though, if retrologue is near it in any way at all, ill be happy!