I have two Hollis DC1 first stages and two Hollis 212 second stages. The regs are 1 year old and the annual service was done by Aquatic Sports. Both first stages are DIN. $300 each or $550 for the pair, OBO, includes shipping to lower 48.
This link is for features and video demo of the regs... Hollis DC1 212 Balanced Regulator - DIN 240.3152.07 with reviews at scuba.com
This link is for features and video demo of the regs... Hollis DC1 212 Balanced Regulator - DIN 240.3152.07 with reviews at scuba.com