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I'm using a SRAM X0 10sp mech on a 42t cassette on my mtb. Hanger geometry dependent, but any SRAM mountain mech should do it.
This is my new favourite thing for all-road bikes
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F273448013341
Mountain derailleur geometry and SRAM Red quality, with a lower profile and better routing.
Total cage capacity might be your only sticking point with 11-40 and two chainrings.
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Currently also using 5700 shifters, but with a M772 rear mech, which is 9sp but works due to same cable pull ratio etc.
Good link here: https://en.wikibooks.org/wiki/Bicycles/Maintenance_and_Repair/Gear-changing_Dimensions#Rear_Shift_Ratios
Next question.
What options are there for a SRAM/Shimano 2x 10 speed road rear mech that can get up to 36T?