Used to get very good results with a Push kit in the Van. Dunno if people are still doing that though?
TF don’t have a price against it, but IIRC the Van was basically a DHX5 without the pressure and volume adjustments so they should be able to tune it that way. Regardless, like most shocks there was a shim stack on the main piston which could be tuned, the external adjustments are just fine tuning.
IMO simple shocks with custom tunes work as well as overly complicated shocks anyway. Yes you might not have the perfect tune for a trail center one week and the Peak district the next. But equally you never have a self inflicted wrong tune for both!
Ask TF, they sell, service and tune both so you should get a decent answer out of them.