Shining Soul II is brilliant !
So I would recommend buying this game although there are a few flaws but nothing you would be let down by on a Gameboy Advance SP.
The flaws are quite annoying repetive sound effects, which don't really test my patience, so that's okay. The next flaw is one of the end bosses who is hard to kill and the fight with him does not really seem to fit with the consistent fighting style throughout the game. This is annoying as I couldn't defeat him so got put off the game and stopped playing it, although when I have someone from Gamespot help me I will be back playing it. The third flaw is that its quite easy, and although as difficulty settings you may well of completed the game in a couple of days. I still haven't completed the game but thats just because of one boss.
The pros. The market system is fun, so everything you can collect can be sold to buy more health and the graphics for this are superb and interesting too. You can also trade on multiplayer and do the quest together, although I have not explored this option I don't think that there is a problem with it, as its a very well laid out little game and very professionally developed. Nice One !