Happyslug, the vast majority of us who own civilian AK lookalikes own them because they are neat, reliable, fun-to-shoot carbines that don't beat up your shoulder like a full-power rifle would. Not because we are worried about black helicopters and "the gubmint." :)
Here's mine:
* I hear AK's are very reliable and rugged. Are there any models that stand out in particular? Any models to avoid?
Anything currently being imported will be very reliable and rugged. I would avoid anything made by Hesse Arms, which had a reputation for poor quality, but those haven't been marketed for many years.
More money will buy you better fit and finish, though. Romanian rifles like mine are typically somewhat roughly finished but look the most like real AKM's; Chinese rifles are a bit smoother; and the Russian/Hungarian/Polish ones are the smoothest. For the price of a Russian/Hungarian/Polish AK lookalike, you could buy an AR-15, though.
Romanian AK lookalikes come in several flavors. Ban-era Romanian guns were mostly SAR-1's (7.62x39mm), with a few SAR-2's (5.45x39mm) and SAR-3's (5.56x45mm/.223 Remington) in there as well. After the BATFE reinterpreted 18 USC 922.r. to prohibit the importation of guns with double-column magwells, SAR importation ceased and WASR's were imported. A WASR is similar to a SAR, except it came into the country as a single-stack and the magwell was widened to spec after the rifle satisfied the 18 USC 922 parts-count rule. The way to tell the difference is to look at the sides of the receiver, just above the magwell; those oval dimples you see in the side of my rifle aren't there on a WASR.
WASR's imported after September 2004 have authentic-looking muzzles (usually with slant brakes) and gas blocks since those features are no longer restricted by the AWB:
The circled areas are the only difference between a ban-era carbine and a pre- or post-ban carbine.
* Are there any models or variants that are especially accurate? Are there ways to improve the accuracy of a particular AK model? It doesn't have to be a sharpshooter weapon, but no terror guns, please.
The more you pay, the more accuracy you will get. A Vepr (built on a thicker RPK-style receiver) will be more accurate than a Romanian gun, but at an AR-15 price. Krebs rifles (Hungarian, I think) are also very accurate, and pricey.
My rifle will shoot into about 2.5 arcminutes on a good day (1.25" at 50 yards, or 2.5" at 100), but sometimes my 100 yard groups are closer to 5", probably due to the fact that I often shoot really inexpensive ammo (Wolf or Norinco). American made ammunition, or quality European ammo like Lapua, Silver Bear, or S&B, will probably do better.
The short sight radius makes AK lookalikes challenging to shoot as well as an AR-15 (and having an old-Winchester-style leaf and blade instead of an aperture doesn't help), but it can be done. Optics help immensely, and most civvie AK lookalikes have an optics rail on the left side of the receiver for attaching scopes and such (see 1st photo for a mounted POSP 4x24).
5.45x39mm AK's have a reputation for better accuracy than the 7.62x39mm versions.
Russian-made Saiga rifles have a good reputation for accuracy and are marketed as hunting rifles, but they have a straight stock and single-stack magazine. You can swap some parts to meet the 922.r parts count rule and then put on an aftermarket stock with a separate handgrip and open up the magwell, and get a very high quality rifle that way for a bargain price. Or leave it in the straight-stocked configuration if you prefer.
If the best possible accuracy at a reasonable price is your goal, you might want to look at a Romanian SAR-2 in 5.45x39mm. You could probably find one on Gunbroker and arrange with a local FFL to do the paperwork. You'll probably have to mail order the ammo or pick it up at a gun show, but I do that with 7.62x39 anyway (much cheaper that way). You can pick up a POSP 4x24 scope for $100-$120 online.
* I'm large, so a heavier model that fires 7.62mm ammo shouldn't be a problem with me. But are lighter-ammo models better overall?
7.62x39mm is still a reduced-power cartridge, and is only about half as powerful as a full-size .30 caliber like a .30-06. So even the 7.62x39 AK lookalikes don't recoil much. The 5.45x39mm's have a reputation for better accuracy and recoil even less.
* Would prefer a model that is easy to maintain and configure. Would like to swap out butt stock, etc. if needed.
Romanian and Chinese AK lookalikes take standard stocks and such; Russian Vepr's don't, since they are built on a thicker receiver. Lots of different stocks and such here:
http://www.tapco.comhttp://www.tapco.com/product_list.asp?dept=40&last=40&page=1I will warn you that the steel underfolding stocks have a reputation for hurting like heck, not because the gun kicks much, but because any recoil at all is a pain when the stock is a skinny steel rod. I'd rather have a full-length stock myself, or fit it with an Ace adapter from Tapco and put on an AR-style adjustable-length stock.
* Semi-auto only. Don't have enough time, energy, or money to pursue full-auto.
There's quite a price difference:
Civvie non-automatic AK lookalike: $350
Genuine full-auto AK: $15,000 (plus clearance process)
If anyone's asking, I'm just curious. Chances are my wife won't let me own anyting more technologically advanced than a musket, but I want to avoid making some of the mistakes I made last time I bought a gun. I want to be an educated gun owner, not an impulsive one.
Thanks to those who already provided advice, pro and con.
Good luck, and hope this helps. If your wife doesn't like nontraditional looking guns, a Saiga is more traditional looking than a Romanian AKM lookalike, if that makes a difference. They come in 7.62x39mm as well as .308 Winchester/7.62x51 (nearly twice as powerful, for hunting). Dunno if any .223 or 5.45 Saigas were imported or not.
Saiga