A little about me, PADI advanced open water, typically do 2-4 total dives a year nowadays, warm water, typically 60-100 foot max depth, ocean. I've been using the same aeris a1 reg and octo since my initial open water certification in 2012. Took good care of it, rinsed well between dives,and no mechanical issues. Have my first liveaboard trip coming up, so I brought it into a dive shop to be inspected and serviced if needed. Dive shop owner stated he couldn't get parts to change out seals due to Aeris being out of business and the service kits no longer being produced. The dive shop only sells scuba pro regulators. Initially, I purchased the mk-17 evo/g260 combo, but after a little bit of research, I saw this was an older model and had him switch to the mk19 Evo/d420 at his recommendation. This ended up being about $300 more. When I went to pick up the regulator, he mentioned it had to be extensively tuned out of the box. I'm looking for something that's low maintenance and won't cause me any problems out in the field. No plans for Coldwater diving in the immediate future. If you were in my shoes, would you go back to the MK 17 evo/g265 and save the $300 or stay with the mk19 evo/d420? Is there any compelling advantage to staying with the mk19 evo/d420?