I will compare this local, all region version with the Wellspring R1 version, released on September 21st 2004.
Both versions are presented in the same aspect ratio. The R1 version features the same Dolby Digital 2.0 audio option, but has the addition of a 5.1 audio track. The R1 version features the same original trailer and director's notes as the local version, but also includes a brief ten-minute interview with Bruno Dumont . Both versions include trailers of other films relating to the particular distributor.
There is also an R2 version available that features a couple of relevant extras, including a Making Of Documentary (34:16), Interview With The Producer (21:30) and Poster Concepts.
Due to the nature of the film, I don't believe Twentynine Palms would significantly benefit from a 5.1 audio track. The director's interview featured on the R1 version also seems to be rather light on. Unless you have a particular passion for this film, I would stick with the local all region version simply for the sake of convenience. However, if you must track down an alternate version, I would possibly seek out the R2 version for the aforementioned extras.