I've heard they can help a bit especially on a small block. I've only ever used an X pipe on one 1966 buick special with a 300 cid V8 along with headers & duals. Honestly, it didn't really feel any different than any other modified V8's that I ran with straight duals. The least expensive and best performance option on a 2nd gen ram would be to go with longtube headers, no cats, and true duals, either with straight pipe, or straight though mufflers such as magnaflow glasspacks or magnaflow single chamber mufflers. Personally, I like the rip roarin' straight pipe exhaust sound with no mufflers, but I always recommend the magnaflows or dynomax ultra flow welded if you want the straight through performance, and aggressive sound, but don't want it to be overly loud. You can get longtube header collectors with O2 sensor bungs in them so that you can mount your O2 sensors right in the collectors, the longtubes should allow the sensor fitting to be in the right place that the stock wiring harness will reach. Dave