If you're going after that dark drum and bass sound (ala Noisia, Phace, etc.), I'd really consider the fact that the beat-synced moving LFO's are possibly the most important aspect of it. You're not necessarily limited to digital gear to do that.
I've gone after the wobble in a couple of different ways and I've found the most cost effective method is to use an Electrix Filter Factory and any MIDI foot controller to sweep through tempo subdivisions (quarter, triplet, 8th, 16th, etc.). The Filter Factory looks kind of corny, and yes it's a rack unit, but it sounds awesome and is way more flexible than any pedal I've tried.
The best way I was able to do this was using the MAM Warp 9, but they're ridiculously hard to find and you'll likely have to sacrifice yourself to gastric for it. Another good option is to find a cheap used Novation Bass Station. It has an external input, full MIDI capabilities, and a killer filter section.