If you want a pre-set your best bet would be a low pressure (blue) Crossfire. That's what WDP recommend and what's used by most teams out there (over the WDP branded PMI one). Grab a CP or Eclipse rail/asa and you'll be golden.
Adjustable, hmm....I've heard many good things about the Evil Scion system. Good recharge across the pressure range and a nice slick compact design should do the job.