The experience of one person with one vehicle is hardly proof of anything, except that there is no 0% "nada-odds".
Unlike Subaru, Nissan and Honda, the Prius uses planetary gear system with no pulleys nor belt for its CVT in pretty ingenious way. Volt uses a similar scheme as well. As you know, planetary gear systems are the bread and butter of traditional automatics.
My wife drives a Prius and hers is pretty reliable so far. We are planning to trade it in soon, perhaps to a Mazda 3, if I can have it my way. The Prius is no fun to drive at all. The CVT has many of the bad traits associated with CVTs in general. However, on normal driving it really does not matter that much, maybe except going up a steep hill.
Nissan is using JATCO CVT units, which are not used by Honda, Subaru. They had a few years of much issues and consumer complaints and you'd be smart to avoid Nissan for a little longer until these issues are completely behind Nissan.
For Subaru, I heard absolutely no complaints since their Outbacks started using CVT in 2010. Most people are even not concerned with the way their CVT behaves differently than a traditional automatic AFAIK (I've been monitoring Subaru forums for a while). The Impreza got the CVT in 2012 and so far there were only anecdotal complaints, especially for the 1st year of service, which was fixed by a software update.
Impreza fuel economy has overall been underwhelming. *Many* owners have complained about barely meeting the "city" economy on the highway. This is also apparent on Fuelly.
In particular, it seems that CVT owners are less happy about their MPG compared with manual owners.
Foresters got the new FB 2.5L engine first in 2011. This engine is now used across most Subaru products, with Impreza getting FB 2.0L variant. In that year, the fuel-economy of Foresters was essentially the same as the out-going EJ engine. However, when the 2014 Forester got the CVT (with same engine) it's average economy rose about 2 MPGs, based on fuelly, only 1 MPG below EPA estimates.
There are rumors that somehow the bigger 2.5L FB is somehow more efficient than its otherwise identical 2L FB. However, I don't know of any credible evidence.
This engine also suffered from OIL CONSUMPTION in the Forester, Impreza. Subaru issued TSB / replaced some engines, but there is reason to believe this engine is still susceptible to some oil consumption in MY 2015.
For Honda Accords, which started using CVT in 2013, it seems there was one recall which affected some vehicles. There are people which complain about transmission whine. Perhaps there are more issues which I am not aware of.