This is my opinion only...
I recently bought a new GME GPS 450...a new release basic chartplotter against the recommendation of the retailer who said it was way overpriced for its features. Bought it anyway...then discovered the front cover was too big and wouldnt stay on under any circumstances...appeared to be from a larger screen and an insert had been fabricated in an attempt to make it fit this unit....this was really cheapo so I took it back...and swapped to the unit the retailer had recommended at the same price.
Then I needed a VHF...looked at GME GX600 flush mount....$269 without DSC and $380 with DSC.........so I checked out Cobra and got a fully featured DSC flush mount model for $199 plus $6 postage....(online from Brisbane) Just installed it and it works just fine...applying for my MMSI, hadnt intended to go DSC but getting it for free might as well check it out. Cobra looks well made...all made in Asia anyway. I have had poor experience with a GME product before so I guess I am no longer much of a fan after this.
Needed the radio because the three year old GME GX600 in the boat was mounted somewhat exposed (under the shelf of the centre console) and the display had failed and gone black, the side knobs were so badly corroded that they had to be broken off...final solution proved to be angle grinder........ as a comparison the Cobra is waterproof to IPX7 (submersible for 30 secs)