Here’s a plug-in from German developer Vengeance called Metrum. It’s for Mac/PC, costs $200 and gives you a computer generated sub-oscillator, mixes it with a few sample layers and has a mod-matrix and randomizer solely for creating kick drums. For those all ITB (in the box) it could be good however I think your money is better spent on a Jomox MBase 11.
“Kick Synthesizer VSTi / over 330 Kick Drum Presets / over 1800 Attack Sample Presets / over 150 Sine Oscillator Presets / ability to integrate own WAV samples / realtime & smooth graphic envelopes / flexible pitch & velocity routings / play tonal kicks! / huge mod matrix with every parameter / every presets comes with assigned modwheel and 3 GUI controls / GUI control knobs freely re-nameable / 6 high quality effects built in / 2 filters for every layer / 3 drive distortion models / 2 band parametric EQ / randomizer function / all parameters automatable / output limiter (you can turn it off if wanted) / 100% timing accurate and click free.” – vengeance-sound.de/eng/VPSMetrum.html
For more info: vengeance-sound.de/eng/VPSMetrum.html