From personal experience, I have been involved with the JWs, a few different "non-denominational" churches, and the RCC. Doctrinal fears aside, I can say the biggest difference I've experienced between the JWs and other christian churches is that I haven't experienced mind control, guilt, shunning, or conditional love in other churches. Although the churches do believe in hell, I've never been to any "fire and brimstone" podium pounding services like the JWs want to believe happen every Sunday in other churches. I'm sure those elements exist in certain christian sects besides the JWs, but I haven't personally experienced it.
The JWs are a legalistic "works" based religion and your level of spirituality or guilt is based upon how much you do, and thus, your salvation is based not upon belief in Jehovah, but how much you do for Jehovah. A JW's spirituality, no matter how genuine, is still an outward showing to constantly prove to everyone around you and Jehovah, that you are, in fact, spiritual. The constant "end time" theme of this religion is always pronounced and at the forefront in their beliefs because this is just another control tactic.
The RCC, again from my perspective, is a sort of belief in Jesus mixed with some church legalism and control. Their salvation equals, half believing in Jesus, and half believing in the RCC tradition. However, I haven't seen any mind control in the RCC that is so apparent in the JWs. I also have not experienced any form of shunning of individuals who have decided to leave. Although they do believe in the Bible, and thus believe in armageddon, it is never a hot topic or rarely even mentioned. A rank and file member's spirituality, is just that, their spirituality, personal and inward.
"Nondenomination" churches that I've visited, are simply, believe in Jesus and scripture alone, and salvation only lies in that, for there is nothing that a person can work at to gain it. I also haven't experienced any form of mind control, guilt, or shunning. "Levels of spirituality" are not pronounced like the JW religion and there are no back room reprimands or losing of duties. Again, like a rank and file RC member, a person's spirituality is personal and inward.