Up until 1993 most if not all of the Imprezas were FWD, then as far as I know, they started producing all of them with the legendary AWD system (even the L models). The Impreza line did not come with a factory turbo until they came out with the WRX in late 2001, early 2002 (MY02 bugeye), but they are a bit heavier than the older Imprezas. Subaru put the 1.8L non-turbo in the pre-93 Impreza FWD, then started making the L with the 2.2L non-turbo, then eventually came out with the RS in 1998. The 1998 was a DOHC 2.5L with AWD and the 1999-present were a SOHC 2.5L with AWD. Through these years, they still had the L model, so you have to be careful of exactly which model you come across. The RS will have an EJ25 engine code.

In my opinion, if you are thinking about buying a Subaru, DO IT. The Subaru community is one of the most plesant communities to be around, and no matter where you are, we see eachother and give acknowledgement. If you want turbo, the two best things to do would be to either buy a WRX, which is nice if you like a 4 door ... or talk to Craig and have him look into doing a swap (you can get either a JDM STi or even a used USDM WRX motor pretty cheap). He's a good guy and he works for his customers... you definitely get what you pay for with him!!!

Sorry if i repeated any other information, but I was too lazy to read the other posts... Hope this helps, and don't hesitate to ask the community questions, you'll usually find some good people, barring a select few!