I'm really on the fence for my next SUV: Exp or Tahoe....
For a pre-owned vehicle, the Tahoe would be easier to work on. Even with AFM (and now DFM), it's comparatively easy to remove the heads. If you have to do that on an overhead cam that would be much more difficult.
I've had the similar coolant issues with a 2008 Explorer and 2002 Tahoe. Tahoes tend to go through the nylon fittings, and I believe the Explorer has them too, but they haven't gone yet. The Explorer has the Y pipe feeding the rear heat. It happens to pass right beside the exhaust manifold and can burn through. We almost has a disaster with that pulling a trailer up the grapevine. It held until we got to our campsite, where it was dripping constantly. That was a $1200 US repair at Ford Orange, which had to be redone back here in Canada because they installed the new pipe touching the manifold. It burned through in a year. The rear heater line hose clamps rust through, causing leaks.
The Tahoe had a leaking thermostat gasket, cracked head (I wasn't happy about that!), cracked nylon coolant adapter, water pump.
So, they have both had their share of problems as they age.