It really depends on your residency desires. I only took the comlex and I feel I experienced more discrimination than I anticipated. I scored pretty well (85%tile step1 and >90th %tile of step 2) but failed to receive interview invites from many of the larger "more prestigous" institutions. Specifically, I was not invited to UVA, Wake, Duke, MUSC, nor Hopkins despite what I perceive as excellent credentials in all other areas of my application. All of my applications were limited to Maryland, Virginia, NC, and SC thus I have no ability to comment outside those areas.
If you will be happy at a "non-name" academic program or many of the better community programs in the mid-atlantic then you will be fine with comlex only, otherwise I would take the USMLE. Good luck with your decision.