Well as the Alero Chapter Secretary of OCA I can tell you that the Alero is a fun car to drive. In 2004 both motors ava are good motors. The 2.2 Ecotec motor is pretty much bulletproof on the bottom end due to the way the motor is made. the 3400 motor may have a problem with the lower intake manifold gasket leaking (refered as the LIMG problem) this is not a new problem and has haunted the 60* V6 motor for close to 20 years all the way back to the 2.8 motor.
If you are looking for a collector car, I suggest one of the Final 500's. They are all dark cherry in color and have speical stiching on the seats and logos on the rims and trunk lid. I wouldn't suggest one of these as a daily, if you want to keep it as an investment. A daily driver investment would be a 2.2 eco with the 5 speed manual. This is a very rare combo. The tranny is a Getrag which is a pretty good manual tranny, however this transmission is only ava on the 4 cyl motor.
The 3400 model is a pretty good car too. I bought mine brand spanking new in 2000 with only 6 miles. Now at just a tad over 93K it's still a good runner. I do use Mobil 1 syn. oil. I hear the the life of a 60* V6 is only 150,000 miles, but over on Aleromod.com, where I am a moderator, there are a few guys with close too 200K on thiers and one guy claims a touch over 200K
The Eco and 2.4 twin cam motor (2.4 product stopped in 2001 and this motor was an updated version of the 2.3 HO motor that was in the 1991 442) have been known to last a while too. Another Aleromod member has an aftermarket superchager on his 2.4 and NOW he's looking to rebuild at 187K.
For a daily with no planed modifactions all 3 motors are good and keep the oil changed and watch that leak on the 3400 motor and they are all runners. With modifactions the 4t45 tranny in the 3400 and the 4t40 tranny in the 2.4, 2.2 are the weak points. I personally blew up my tranny at the track, but I still drove the car around for a week afterwards before it started slipping and giving me problems. I lost all 14 quarts of tranny fliud by the end of the week
The other little problems with the Alero are simple easy fixes. The blower motor resistor is known to burn out is you use the climate controls on 1 or 2 regually, The anntenna / rear window defroster is known to burn up and not work and the fuel pumps fail, but all those problems are common GM problems, not really the fault of the Alero itself. The fuel pump is a bit tricky to do without a lift, but the resistor and rear window defroster are fairly easy, they are just a bit of a pain to get to.
I an in the process of getting my Alero's hood and fenders repainted. 8 years of road rash left a lot of little nicks and stuff,
but that's normal for any car.
The GLS model is the top of the line. These cars are loaded with all the bells and whistles and will have leather and a sunroof. After 2001, they came with an upgraded stero system with a Monsoon amp in the trunk behind the carpet on the left side of the trunk. The GX would be the base model would be bare bones and GL model, pending on which one you get GL1, GL2, or GL3 will have some of the stuff that the GLS model will have.
Don't know what part of the country you are in, but we have our own car show behind the Holiday Inn on Saganaw Highway in lansing, MI on the Firday before Homecomming on the state capital grounds. I help put on that show. The date will be June 13th and Hommecomming is June 14th. Anybody here is more than welcome to stop by and say hello. We will all be in "Street Stock" at Homecomming