Tom, thanks for your comments, sadly the offer on Gooutdoors is for the S/M size - I'll need the M/L. I know that Bob Cartwright sells them and I may pay him a visit in Malvern as I bought the Gossamer rucksac from him 3 years ago.
best wishes Colin

I carried the Grand Tour for (I think it was) three Challenges - nice pack but the stretchy pockets kept catching on ******* things and needing mending. Also it had a clip on the hip-strap which didn't stand up to constant use, and which failed one day on the hill - awkward. However, with a replacement buckle it was great. Perhaps they have now got a better hip strap clip on the pack. I know I wasn't the only person to complain about it.
This year I carried the Mariposa on the CWT and Challenge - I LOVE it, especially the big stretchy pocket and the hip belt.

Lindy,

thanks for your helpful comments. I too love the practicality of the Mariposa, but it is not quite the right fit as I carried the weight on my shoulders for the Challenge. I'm going to look at the Osprey Exos before trying the GT. All the best Colin