We have recently moved to Salisbury and I am worried about the alternatives if DS doesn't pass the 11+. On first impressions, none of the boys secondary schools look too great, with below average results, and obvious lack of investment - completely in contrast with Bishops, which gets excellent results and has clearly had a huge amount of investment.
The non-GS state schools in Salisbury are indeed fairly mediocre, unfortunately. If your son doesn't get a place at Bishop's, the only sensible alternative is to look at independent schools, if funds allow, or other counties.
You should also bear in mind that the 3 schools at Laverstock may become some kind of academy thing in the near future, and if that goes ahead, there'll be a lot of changes that the kids could really do without. For this reason alone, I would rule out the non-GS options in Salisbury for my kids (at least for the next few years)
Even looking at independent schools, none of them really stand out.
I guess you're referring to boy's or mixed independent schools here ? Godolphins has a pretty good reputation.
I'm not that familiar with the independent situation in Salisbury, however, so I'm not best placed to comment. If you're considering independents, don't forget to look at Dorset, Hampshire, and even East Zummerzet too, as there are several places within reasonable travelling distance. (Because of the plain, it's easier to get to these places than quite a bit of the more northern parts of Wilts)