I built up the Open Wide. I have two sets of wheels (Easton 700C) and Hunt (650B). I selected the AXS mullet system as I was using it on my MTB and it works flawlessly. I did a ride from Cape Town to Plett in December which covers about 700km of gravel roads. The bike worked fine and the 650B wheels worked wonders to take the sting out of some of the rough gravel roads especially when the temperature climbs above 40C. Some of the mountain passes were very steep and rough and the gear ratio was enough to tackle the steepest ascents without giving away too much on the descents. The new diverge has just launched so I will pick that up next week and see how that compares. At the moment we are only allowed 5km for our homes between 6-9 in the morning. Couple of cyclists have been arrested for cycling after 9 so not much chance of going for long rides any time soon.
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@timeforcrime thanks for the link to the Garbaruk rear derailleur thatās really good being able to extend the 10-33 to something actually useful for 1x
@jct that blog iāve read before. it also said they tried it with a 11-39 Rotor which also worked fine. Didnāt mention the 11-36 Rotor but the Garbaruk option may likely work with that as well
Ended up just going with an XX1 rd instead of messing with the Garbaruk cage.
Sram 42 chainring, Rotor 11-46 cassette and KMC X12 chain. Seems to shift great outside and on trainer. Feels a little faster than Force rd. Nice and quiet. Very happy with the switch.
I would put together a comparison of the geometry of each bike you are considering. Different bikes have different feels to them. Some will have a more aggressive geometry with more of a road bike feel and others will have a more relaxed geometry. Depending on what type of bike you want, this should help you narrow your choice down.
Also, it may or may not fit your current preferences, but the 2021 Specialized Diverge was what I chose. The āPro Carbonā variant comes with a SRAM Force AXS 1x drivetrain, which Iāve decided to change to a 2x (46/33 chainrings and 10-33 12-speed cassette). Thereās also the 12-speed 10-36 cassette with a little more range, or the 1x options.
Given the right tires and wheels, Iād expect this be a fast option and quite comfortable. Note that Iām a beginner rider and have taken a great deal of adviceā¦ this should be interpreted as something you should investigate, not an expert recommendation! 
How are you liking this cassette? I am considering moving to a rotor 11-46 or 11-50. The gaps on the SRAM 10-52 are too large for me.
Sometimes I notice the gap going from 13 > 15. Wish there was a 14 but that would mean one less climbing gear so 
The 11-39 does have a 14 but sounds like you want some smaller gearing.
I was worried about the gaps when switching to 1x but it hasnāt been as much of as issue as I thought it would be with my current setup.
I am currently in the process of building up a gravel bike, that is 80/20 road/off-road. I am very likely going with the SRAM Force AXS WIDE. I love the rear mech on my ĆTHOS, and with the smaller Chainrings, it just offers amazing range.