My young dog seems quite happy for me to clip her nails, but the cheap and cheerful clippers I have are not really up to the job and the more I fiddle the more fed up with it she gets. What clippers would you recommend for a large breed dog?

If you've got the Mikki from PAH then they are rubbish. 
I use Resco guillotine and they are many many years old, still the ones that I used to use in the grooming parlour and not even a new blade. :)

How interesting that you should say Mikki from PaH, guess what!

I will look up your recommendation, than you.

Me too use Resco - the 747 Jumbos for my Bassets.   And have done since the start, obviously with replacement blades and occasionally a whole new clipper.   I did try the scissor type but didn't get on with that.   I use big human toe clippers for my Whippet's dainty nails however.

When I used to use nail clippers I could never try the guillotine type, alway the scissor type. I only ever clip baby puppies as I am much happier using a dremmel...dogs are too :)

> as I am much happier using a dremmel

I use a dremmel with one dog and a pair of my OH's electrical wire cutters for the other dog :)

>I use big human toe clippers for my Whippet's dainty nails however

:-)

I use them for Chihuahuas and Yorkies.

Have never managed to get along with guillotine clippers especially with really tough nails, but it's all down to preference. Use the following & would buy again.
http://www.galaxystores.co.uk/nail-clippers-heavy-duty-green-handle.html?gclid=CMvd4e2L-LgCFYfMtAodmGsA4g

Once again, many thanks to all the replies, they have been very helpful and I have ordered a pair of Resco 747's.
I've found this forum to be so useful for all sorts of things and have learnt a lot on the way.