Is the 65 worth getting over the 60? The 70 seems to have proprietary digital, which isn't compatible with other dmr?
The FT-60 is approximately 15 years old. It's a reliable, well-proven radio. About the only things going against it are size (compared to newer radios) and its nickel-metal-hydride (NiMH) battery which is a bit heavier than lithium ion batteries used on newer radios.
The FT-65 has been on the market approximately 2 years. It's a much newer design, but seems to be garnering a decent reputation. It's smaller and lighter than the FT-60.
Yaesu System Fusion, the digital voice mode that the FT-70 offers, is not compatible with other digital voice modes used these days, but it is not proprietary. However, Yaesu is the only radio transceiver manufacturer to offer System Fusion.
Any amateur radio transceiver that can transmit outside of the amateur radio bands, with or without "MARS" modifications, would have to be FCC type accepted for the applicable parts of the FCC rules (Part 80 for marine radio, Part 90 for business and public safety frequencies or various sections of Part 95 for GMRS, FRS, or MURS). Most radios intended for the amateur radio market cannot be legally used to transmit in Part 80, 90, or 95.