The pump strock on a sniper is alot lighter usually and sometimes this gets mistaken for smoother. Phantom pump strokes are not bad at all but the are nothing to brag about. The smoothest nelson I have ever shot was a ghost. Its pump stroke is super nice. I did t the phudard mod on my phanomt and not it has no twist at all.
Phantoms make awesome open class guns but they feel alot diffrent than a sniper. For an openclass phantom I like vertical air with a 3.5oz tank, center feed breach, Ego feed neck mod, T stock and a 50 round winchester.
I am not a fan of packs that go on your back for stock class. You will be reaching back there to get a tube every 10 shots then after you put it in the gun yo have to put it back in the pack. For a pod that is no big deal but I think its a pain in the but for 10 round tubes. I use the PBmafia LG10 leg harness and it works amazingly well. Its super easy to grap a tub, fill your gun then put the tube back. I can not vouch for how it does with twelve grams because I allways use a 3.5oz tank.