Sorry, just to clarify, I did not fall on my first ride with them, but after about 7 months of approx 10-20 miles of combined firetrack and singletrack per week (still unlucky, but not quite a 100% crash record!)
Many thanks for the suggestions/comments. A bike swap is probably not going to work well as I would be swapping with £800+ machines with combinations of 29″ wheels and FS so very different from the budget Carerra I am looking at. That said the Giant Revel I hired last week is a similar value so may be worth haggling for a weekend hire
Skills training is also thought. I have read the many Jedi recommendations, but dismissed him as way too advanced for me. My riding buddies are very experienced and one has done some MTB leader courses so I get (hopefully) good advice from them, but perhaps paid for advice is worth looking in to
I also like the comment on max comfortable speed. I think I will be applying that when I am finally allowed to get back on two wheels. Previously I just tried to keep up with the fastest person in the group
Cheers all!