I've only been using my ACI Assassin for about 3 weeks, and it's pretty good. I like the heft and the stability this marker provides. I took this down to DuPage, and it did really well. No clogs, jams, or chopping. The battery lasts a long time, and i've put a case and a half though it so far. The only real complaints about this marker is that it's expensive for a low end electro, and the grips are far too slippery. If you're gonna buy this, get stickys for it.
Overall, It's a good buy, and besides, ACI Splat Factory uses this.