I also own both bindings. I agree that the Forces are more responsive. They are also noticeably lighter IMHO and are more durable (wear and tear after equal abuse periods is somewhat higher on the fluxes). I also find the Forces are more comfy to step on because its got more cushioning and that EVA bed is more damp at speeds. Now that they tweaked their ratchets I'm ok with them and I'm indifferent between the ratches on both the Forces and the TT30. Downside of the Forces to me is that the way their highback is shaped does give rise to some calf bite if you do like to rotate your highbacks.
On the TT30, I dont find their straps take too long to get into and have a more "pillowy" feeling that is more comfortable if you are strapped in for long periods (Unions sometimes give people unwanted pressure points). But I find that precisely cos of this, they are not as responsive as well. Same goes for their rather bulky but comfy highback. Big downside is heelcup adjustability (you cant adjust it),but you can adjust the heel and toe ramps much better than the Forces (which just has an option to extend the gas pedal by an inch or so, which I dont like cos its like ur toes are pushing on air). I also totally love how easy it is to tweak the entire binding without a tool (the Union heelcup, toe strap, toe ramp and highback rotation all need a tool - adjustment on these for Fluxes are tool free).
Between the two, I ride my Union Forces way more (but thats just me, I dont know what you are like). But if you are a big comfort and ease person when it comes to binding fit, feel and set-up, I'd say go with the Fluxes. Unions are very hit and miss for lots of folks. They usually either like it (alot) or think its hype.