Finally back on the road today, after the FRM spider/Specialities chain ring failure:
I remembered I had some Topline cranks (in their original box!) that I had initially bought for the Karakoram, so I got a Stronglight chain ring for them and the bike can return to being my main ride:
By deviating slightly from the optimum chainline I've been able to switch to a 42T chain ring, replacing the previous 38T, so hopefully I'll be able to break a few of my best times (or find my legs aren't up to using top gear).
Just seen I didn't ever answer that, I love the position created by the upside-down Marys, it's very similar to the hand and wrist position I got used to on my motorbikes when I was younger. The Phorm grips I've switched to help too, as they are specifically designed for swept back bars:
Furtherest I've ridden in one stint on this bike was 88 miles and my hands and wrists both felt fine at the end.