If you're looking to buy a TV with good bang-for-buck then a Vizio is usually a good choice. For example, the Vizio M3D550 offers a picture that rivals the excellent Sony HX850 but for half the price. But despite having a similar name, the 65-inch M3D651SV doesn't share the 55-inchers' giant-killing traits. Instead, what you're paying for here is pure size.
The picture quality of the M3D651SV is inferior to TVs of a similar price and size; while the color is acceptable, black levels aren't as good and shadow detail is slightly crushed.
Design is also a weak point, with a dated-looking bezel and the lack of a swivel stand. Further, the TV is quite reflective, and this can prove distracting in a lit room.
If size is unimportant, then I'd say go for the cheaper M3D550KDE, or if you want a big screen then try the Sharp LE640 series. Both offer a better picture than this.