Yes, I would agree on Dacor, steer clear, especially if you intend travelling internationally, distributors are few and far between and usually only carry parts for the lines they stock, which may very well not be your reg, old parts are almost unobtainable.
Certainly, from an international travel view ATOMIC is nowhere near as strong as US DIVERS (AQUALUNG) which is well supported the world over, but if you are only looking domestically, I guess either are great.
As for gauges, well, none of the brand manufacturers make gauges, these are all made by various OEM companies and branded with the name,...................they are all much of a muchness, look for one that suits you and dont worry about branding.