I don't completely trust the Ofsted reports. I would say that there's no simple answer, as each school suits different types of personalities.
Southover is very academically-oriented and has been described as the next best thing to private education. Good for bright kids. However it's a bit poky and the playing fields are shared with Western Road. Also, if your child isn't academically precocious and likes running around, this isn't the right place.
Western Road has lots of artistic/bohemian parents. It's a close-knit school that has suffered from poor leadership in the past and I know of a couple of parents who moved their kids from the school.
Wallands has the best location - lots of open space. Academic standards are pretty good. It is quite 'mixed' (i.e as many chavs as middle class kids). The SENCO (special needs) co-ordinator is pretty useless and there have been complaints about the headteacher, although others say he's improved the school during his tenure (he's leaving in the summer). Good for normal, average children. Most teachers are good.
St Pancras - Catholic, but they don't ram religion down your throat and accept non-Catholics. It seems a happy place with good standards, but the playground area is tiny, sandwiched between two roads.
Pells - poorer academic standards due to the catchment area, but results are going up.
I've heard good and bad things about every school and when I was choosing, ended up feel more confused than ever. Good luck!