In a nutshell, Vortex is the best in terms of absolute flash suppression with the Phantom being a very, very close second. Tines of the Vortex can catch on brush and it can kick up dust when prone. The tines are tougher than what some people think, at least if you have a genuine Vortex. There are copies out there, I would avoid those if you can. The latest Phantoms have the bottom sealed so there isn't the dust problem and they probably act as a compensator in a minimal way. They can be had with the tipped front for poking if that's your bag, and all Phantoms are closed in front so no brush catching problem. The Vortex can enhance accuracy, significantly in some cases apparently. Both are standard dimension so they can take muzzle attachments. Phantoms are cheaper IIRC.
My recommendation is the Vortex. But if you are going to be going prone a lot on dusty environments, or running through the bush, get the Phantom. There are other good flash suppressors but they are way behind these two. Both will also bring your 14.5" barrel out to 16".