Old WRX buying issues

So I am currently in the process of researching the Subaru Impreza WRX and potential cars in my area. Throughout my time researching I noticed a trend in many of the older Imprezas and their engines. I have wanted to own a WRX for a very long time but have not been able to as I still owned a car as my daily driver. I have since sold the car and moved on to the WRX ( a car I loved early in life). A 2002-2004 early Subaru Impreza WRX has been the target of mine as I like it's preformance, cost, and availability of customization. My plans were to buy and use the car for a full year or two before I modify any internal or external aspect. Problems ensued when deciding on the many choices that my craigslist offered. I want to buy a wrx (early year for a cheaper price) with lowish miles (120k miles or less) but noticed with many of the better deals on the site is that often owners will buy JDM engines and swap out their broken stock subaru boxer engines. Basically I wanted to reach out to the Subaru community and ask what are the quality of these JDM engines, how long they will last, and in general if cars with these JDM engines are worth buying. I really wanted to buy the car locally through craigslist but can't find any wrxs with lowish miles that still has the stock engine. Most that do have the stock engine look pretty worn and have well over 130k+ miles while JDM engine swapped cars are 30-80k miles and look a lot better. It would be even better to talk to someone who had bought a old impreza wrx with a jdm engine swap and what are their experiences.