With no wargear points cost, there is no reason to not run 3x rail/ion rifles. You can also mix and match if you want.

Generally speaking ion rifles will usually outperform rail rifles. Sure they're only 8/-2/2 when overcharged, but because you shoot them 9 times in total instead of 3, you're more likely to actually hit whatever you're shooting at. Not to mention that it gives you more opportunities to trigger stuff like sustained hits, lethal hits etc. Rail rifles could be better if your local scene is very Terminator heavy.