RadioXtuner is one of the best tuner techs in the country. It just boils down to how much your tuner is worth, and how much you are willing to spend.
If I had a Marantz 10b, a Day Sequerra, or a premier McIntosh MR71, I would turf it to Mike Z in San Diego. The $800 plus surcharge would readily be covered at sale time.
RadioX in Michigan would get my primo HhScott, REL precedent, and Rhode Schwartz.
Mike would get all the other hifi and midfi tuners, including my Yamaha tuner.
The calculus on performance/cost/shipping leans heavily toward local.