Well, I felt I'd share a little experience I've had with my recent helmet purchases. I've had the Gmax for about a year now and the Summit 3.0 for a few days. I'll try to hit the key points to each and feel free to ask any questions.
Purchased for $127 from compacc.com. I bought this helmet to replace my aging Vega Summit XPV and noticed this was a very feature-packed modular helmet at a very affordable price. It offered an internal sunvisor, speaker pockets, easy-to-remove visor and lining, and the dinky light in the back.
It is a damn good quality helmet for the price. I was surprised to find the modular mechanism has actual metal hardware and offers a very crisp latch mechanism and easy one-hand operation. However, I found it to be very noisy on the interstate and after about half an hour it created a pressure point on the very top of my forehead. I removed the liner and sanded/massaged the area to better fit my head and have made it work pretty well.
The visor is very, very easy to remove and the visor itself seems very sturdy. As hard on equipment as I am, the visor still looks just as nice as it did the day I bought it. It cleans easily with soap and water, and doesn't seem to scratch easily at all.
Overall, this is a great looking helmet and superior quality for the price. I have been impressed with this helmet in almost every regard except for touring comfort and wind noise. Other than that, this helmet is a keeper.
VEGA SUMMIT 3.0-
Purchased on eBay for ~$110 shipped. I had very high hopes that this helmet would be as quiet and comfortable as my Vega Summit XPV. However, it didn't fit the bill at all. It is very comfortable to wear, as comfortable as my former Shoei RF-1100, but holy cow it's noisy.
It makes a dull roar even riding in town, and sounds like a hurricane on the highway. The modular mechanism is an absolute joke. It has plastic pins that slide in/out to 'lock' the helmet down. The drop-down sun visor doesn't come down far enough and gets obnoxious, not to mention it feels like I'm about to break the tiny tab that controls its position. I have had to slam the flip-up face just to get it to close properly, and it certainly feels like it won't be able to take this abuse constantly.
Overall I'm very disappointed with the Summit 3.0. I've looked up a few videos and it looks like the guys nearly break the visor getting it to come off, yet another thing I'm not fond of. The few times I've ridden with it and just cracked open the visor at a stoplight, and whenever I'd go to close the visor I'd have to make multiple attempts since the detents were very defined (due to being new) and the visor was thin and flimsy.
So, I have 3 helmets that all have something they're better than the other at. The retired Summit XPV was one of the quietest helmets (full face included) I've ridden with, the Gmax felt the most sturdy and best built/featured of the modulars) and the Summit 3.0 is one of the most comfortable/plush helmets.