The TLDW; is you can now trial ANY DCS module or moduless for 14 days for free. After the trial has completed you can't then trial that same module again for 6 month BUT you can the trial any other module(s) for 14 days.
So if you're happy changing planes every 2 week you can now use DCS entirely for free.
(This only works on the Stand Alone version and NOT Steam)

Plus if you are a new customer you get 50% off you entire first order.