That's the first time I've ever heard someone say that you're prone to breaking your neck because of a full-faced helmet! Let's get with the facts, and not with opinion:
1. Half-helmets and 3/4 helmets are both decent protection (provided they have at least a DOT or SNELL cert), but a full-faced helmet will protect you even better. There's no point in disputing that due to the fact of the design differences...full-faced + no exposed jaw = better protection.
2. People that complain of getting hot in a helmet bought the wrong helmet. The more ventilation the better, and it doesn't have to cost you and arm and a leg to obtain that. I recently tried my old half helmet for a 30 minute ride and I had sweat running down my face. Did a two hour ride with my full-faced helmet, and the lining was bone dry. And yes, this was in 85+ degree heat.
3. There is no limited vision in a full-faced helmet. Strict regulations have forced manufacturers to maintain a minimum viewing angle, and most not only comply but exceed that standard. I believe the current regulation is minimum 160 degrees, which encompasses just about any normal person's peripheral vision.
4. As for twisting before getting into an accident and avoiding the chin?
Statistically speaking, anything short of a full-faced helmet is leaving you much more prone to getting into an accident.
Those are the facts, not opinion. As for the noise reduction in full-faced helmets, that's more subjective. It's true, wearing a full with the visor down will lessen sounds around you...but the key is ALL the sounds around you. It's won't selectively only tune out traffic and cars. The best analogy I can give is if someone tells you to turn down the TV - for a while, it seems too low to hear, but very quickly your ears adapt to the change. It may not be the case with all helmets and with all people, but I can tell you that if you crack the visor open you'll be able to hear just about the same noise levels as with a half or 3/4. And the more you open it, the more you will hear.
Don't get me wrong, everyone's entitled to their opinion and I'm not telling anyone to wear a full-faced helmet. I'm just presenting the facts. Definitely wear what you feel is comfortable as long as it fits well - no matter what you decide, if it doesn't fit it won't even help you if it was lined with marshmallow and the outside was wrapped in bubble wrap lol
Now back to his question, you might want to try http://www.motorcycle-superstore.com/5/15/151/DEPT/Scooter-Helmets-Mens-Riding-Apparel.aspx - they have a selection of open helmets that may suit your needs!