The strips from ebay are 3528, and 12 spread over 12 inch.
That diode is one diode on a 4 SMD, where Comets are 5050. 4 times brighter and denser.
A huge difference in light and adjustable in brightness.
In addition, its possible that these were made specifically at 5v. 6.3V is almost 30% more current
then its rated for.
I dont think there would be an issue, but its possible.
The development of the strip to work on AC/DC, (GI and Inserts) in itself took time and errors to get
right.
With up to 20", frosted coating, dimmable, plug and play with Matrix, its really a no brainer.
Consider where you want to use them, and consider if Pads, Cobs, circles, or strips fit your game and vision best.
Ryan and Janet are top notch, and a short wait for stock is worth it.