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.
While we've seen some good Vizio TVs of late -- and I'll include the Vizio CinemaWide XVT3D580CM here now that it's half the price it debuted at (currently $1,399) -- the Vizio M3D651SV doesn't rank as one of these. Although it has a glossy coating as does the 58-inch, in this case it simply serves to cause reflections rather than adding to the perception of contrast. For example, in this photo you can see both me and the couch reflected on the screen. The TV also misses out on a true local dimming system; although this means that blooming isn't an issue, it also translates to lighter blacks. While adding Adaptive Luma helped with the "pop," the TV simply didn't have the guts to portray shadow detail convincingly, leading to flatter pictures overall. Colors were acceptable though a little too blue, but at least saturation was well accounted for with bold yet natural colors.