My setup: Third generation Asus iCore 7 laptop, 8 Gb RAM, 1.5 Tb HDD. I use it with Ableton 9 as a VST plug-in. I'm still discovering things, but Komplete is very exciting, Monark, Massive and FM7 are a slap in the face, the SSL-like audio plug-ins are amazing. It's not too resource-intensive, even if you work with your own patches and you have packed it with effects, although I haven't driven it to the limits (16 tracks), I downloaded the most recent control center and it forced me to enter the serial number again with every element installed. Once you've gone through this and validated everything you won't be bothered again.
Massive give me lots of pleasure, it is THE modern modular. MONARK is amazing in mono, especially with an arpeggiator.
I'm far from having explored everything Komplete has to offer, but it's a must-have for all enthusiasts.