I'm not all that "up" on the current AK-74 rifles, but the Bulgarian's have a good reputation.
I'm not sure about this, but I think some of them have American made barrels, and at least the early USA made barrels had problems.
The top of the line in an AK-74 is the Arsenal, Inc SGL-31 series.
These rifles are built in Russia by the same factory that makes military AK rifles.
These are sporting configuration type rifles named the Saiga.
The Russian factory makes a special version exclusively for Arsenal, Inc that are easier to convert and have more military type stampings.
Once the rifles are imported into the USA, Arsenal, Inc converts the rifles to an AK-74 military configuration.
These rifles have chrome lined bores and gas blocks, and are as close as we'll ever get to a real Russian military AK-74.
They come in a number of versions, with choice of black, OD Green, or Soviet Plum colored stocks and hand guards. Also in two types of folding stocks, and with accessory locks on the barrel, including a bayonet lock.
Quality is the best available today.
Prices are higher, but you get a great rifle. The rifles are sold through big distributors like K-Var, Zander's, and others.
http://www.arsenalinc.com/usa/home.php?cat=
http://www.k-var.com/shop/home.php