While I have used RR and ECU Flash with a Tactrix cable and laptop, it was not 'easy'. Not hard, just kinda anxious. As for the range of models my cable works with, after you get it, you could email Tactrix or maybe the RR group to figure out what it will/won't work with. After downloading the software, you have to do an update for the 'definitions' for each car model/year. I used it to kill 14 codes on my WRX. DO NOT try to use ECU Flash from any laptop that is not fully charged! Also, I recommend getting a cheap flash drive for any car you mod, throw the original rom data and the new data in files on it to pass along to the owner. You might consider putting those files on a cloud server somewhere too, associate it to the VIN? - just in case you need to revert to original.
I see no reason I couldn't mail the cable to you to play around with. JUst keep it on 'permanent loan'. It's unlikely , but, you could just mail it back if I ever needed it. PM me a mailing addy and I will work on getting it to you - could be a week or 2 as we are very busy catching-up on things since my MIL moved out.
as you know, over at subaruoutback.org, PlainOM and others have a thread. You could PM those guys for info too.