I had the same problem when buying a glider, there is very little truely unbiased
input but I think the truth is that many are good these days and as long as the wing
is a modern design you may not notice great differences. It's difficult if not impossible
to "test drive" many so you end up on relying on advice which is OK as long as you
respect the individual it comes from. I bought a glider (DHV1 - Cyber from Icaro
2000) from Dion because I had flown it before, knew it launched well, felt comfortable
on it, and I felt Dion knew gliders well enough that I could trust his advice. There
is also a site (Para2000.com) that lists nearly all gliders and offers links to review
artilces if available. There will be some glider reviews in Paraglider magazine this
month including the Firebird Grid which is a DHV 1-2 I have heard positive things
about.