This is really quite a fun build with good results, especially if you take the time to paint it a little.
Good:
1) Lots of moving parts with all the missile positions
2) Really Big guns
3) It's Heavy Arms! It's just a cool suit!
Bad:
1) Will require some paint to make the missiles and gatlings look right. I'd recommend getting a brush and some water-soluble acrylic craft paint at Wal-mart or someplace.
2) Trowa figure is molded in only one color!
3) Watch out for losing some of the pieces, especially on the leg missiles containers. You might want to glue them down.