We have a 8 month old gr who was enjoying her food, but has over the last week started to turn her nose up at it. I was just after peoples views on middle of the range priced large breed dry foods that we could maybe try. Thanks.

What is she on now?  Do you feed just a complete feed?  Perhaps you could add some raw chicken wings or mince to make it a little more interesting.
I feed my girls on a variety of foods so they don't get bored.

She is on a food called symply, which is a complete food it is quite pricey at £39 for 12kg and I am having to throw it away if she dosent finish it. Tried adding mince and some veggies to it but she just picks these out!!

What about adding gravey that seems to work with our lot... or change to something like James Wellbeloved or Ardengrange, dogs do get bored of what they are fed sometimes we have to change everynow and again just to add some spice to life.

It could be her age, an approaching season, or just that she doesn't need as much as she used to.  I'd be inclined not to swap the complete food but look at the amount she is eating, when in the day she is hungrier, and how she likes to eat it.  Feeding after exercise is generally helpful, mine are usually hungrier at their evening meal and I have one boy that likes his complete to be damp and another that wants the whole crunch.

If she's only been picky for the last week I'd say there's no need to rush your decision.  Here's a few things that helped when mine were on kibble (I now raw feed)

Weigh what goes into the bowl - if needs be you can then weigh what she doesn't eat to work out if she's getting enough.
Warm the kibble in the microwave or by adding a splash of warm water - this activates the smell and should stimulate her apetite
Add some sardines in oil - these are great to get a fussy dog going again and you won't need much
Add a bit of chicken stock or boil a whole chicken til it's gloopy, remove the bones, then freeze in small portions for mixing with kibble.  Best served warm

You may still decide to change her food but it could be just a phase.  In the meantime you could get some trial bags from people like Arden Grange or CSJ to see what other foods might work well for you.  Mine have eaten both of these and still have at least one kibble meal per week cos they like it.  You can certainly combine dry foods or alternate if you (and she) prefer

This is the age in that breed when the majority of fast growth will have already been made, so ti could be that she needs her  food cut down a tad. 

What is her weight like?  Not in pounds but in flesh, can you feel her waist and her spine and ribs easily bu not have them prominent.

If her weight is fine then I would not be messing about but pick her dish up after 15 minutes and give nothing until next meal time. 

If she is plump enough cut her food just a fraction, or just allow the odd missed meal to do the trick until she is keen again, and then reassess if cutting back is needed.

Agree with other posters, add maybe an egg, some tripe, natural live yoghurt etc, (not all at once) :-)
I have never used large breed complete for a GR, just the normal, Arden Grange similar price.

I never use large breed kibble for my goldens only normal.
Mine always have nature diet mixed with their kibble and always have an empty bowl at meal times.

Thanks for the advice, I will try some of the suggestions and also may get a trial bag of Arden Grange as lots of people recommend it, and it looks a very good food for less than we pay now with a bigger bag.