I have played and finished all 3 mother games a while now (finished 3 somewhere in spring). Here's my opinion on them.
1: Very old game. But also enjoyable. I have played a lot of NES games but no RPG ones. Soo this was a fun experiance. The game felt very stiffy, but hey, it's old soo I can take that. My biggest problem with this game is the grinding. Good god. Took me almost 20 times just to rescue that girl near at the cementary at the beggining at the game. And then, we had that zoo right after it. Only luck made me finish that one realtively fast. I don't really like to use it but walkthroughs (reading of course) have helped me save lots of hours. Also, there were many PSI powers that was really useless and never touched again. It's a memorial experiance, especially when closing to the ending. Though it will probably take a long time to revisit this game again, or never. I dunno. I did feel satisfied ones I finished the game. And Polyhanna (NES version) will always play in my head when I think about the mother serie.
2, Earthbound: A very speciall RPG. It's not your typicall middle ages "Sword n Sorcery" RPG game. You play a around 10 year old boy in modern society. You can really feel the atmosfear of the game burning your eyes already at the beggining of the game. It has really no connection with the first game except the phone with your dad, also Giygas that you see before you even start with the game (his name that is). I really like the game but can not put my finger on it and say why. It's very memorial however. You start in Onett, then you visit Twoson, Threed and Fourside. This is about the first half of the game and it's REALLY slow, and not much stick to my head except some of the surrealism. Soo I had mixed feeling first. However, it gets much better. The story however feel kinda weak. "Giygas must be stopped and you, only you and 3 companions that will come on your journey can stop him". Still, very enjoyable. Will probably visit it again. And how much music did this game have? I don't think any other SNES game has half of this games music tracks.
3: I kinda feel for saying Mother 2/Earthbound is the "New hope" version in this serie and Mother 3 is the "Empire strikes back" version. If that makes any sense, dunno what Mother 1 should be. Anyway, why isn't this game realesed here in west yet? This game screams gold. It's perfect, I think. The only complain I have with it is the boring chapter 3, and I don't know if I feel satisfied with THAT ENDING. Mother 3 basically took what earthbound was lacking and made them better.