If you can get both units for the same price, or didn't care about price one iota, are there any advantages to the HR91? It seems it's a newer unit but they left loads of features (mostly ones I don't understand or with slightly rude names) out, and shaved a few quid off the price. I could imagine battery life might be slightly better but is there anything it does better?

I'm about to order 8 units and at least 4 are going onto new Valencia bodies, so those could be either type as easily from what I've been reading.