i am trying to find a superb estate auto 150ps 17 plate to 18, silver or grey, my question is this are the headlights on the se really ok because i seen an add on autotrader and the headlights were really yellow ish.

The bi xenon headlights are fantastic and look nice. If you can I’d stretch to the SEL, you get some nice features over a SE such as denon, leather, heated and memory seats, electric tailgate, privacy glass and keyless entry. 
I’ve not driven with the standard headlights on the superb but the Xenons are a big step up to other cars I’ve had 

yeah i agree with you regarding SEL especially privacy  cars glass, the estate cars without it look weird. my budget is around 16k.