If you're looking for pure quality in a Mauser, some of the contract models are THE very best IMO. Those sold to Chile, Argentina, Brazil and Persia (Iran), among others, were made to a quality standard that is unlikely to ever be seen again. While not a true Mauser design, the Portuguese Vergueiro made by DWM as the Model 1904 in 6.5x58mm and later reworked by Mauser in 1939 to 8mm is of the very highest quality.
Although not as strong as the 1898 Mauser action, the DWM manufactured 1891, 1893 and 1895 Mausers are also of a quality that will never be made again. Find one in excellent condition and you'll have an example of unsurpassed craftsmanship.
Many South American countries were armed with Mausers at a time when the US was still using Trapdoor Springfield rifles and Krags. They were better armed than we were until the 1903 Springfield was issued. The '03 was close enough to a Mauser action that the courts awarded Paul Mauser one million dollars to settle a law suit against the US Government for patent infringement.