I find it easier with one, I don't use it that much for personal use so it felt pointless to have two, and I prefer everything (apps, Facebook, calendar etc) on one phone.
I don't really see the different between your 'personal' phone and 'work' phone being out there and advertised in terms of privacy and inappropriate people because they're both still your phones and if the weirdos want to contact you then they'll contact you regardless.
I don't answer calls out of hours and people don't bother ringing late, if they do I just ignore which isn't a problem as my phone is on silent most of the time anyway. People usually message through Facebook rather than text, and I have my 'away' times set on Facebook so that if they contact me at silly o'clock they will receive an automated message. If its a text then I just ignore until I can reply. I have the 'Do not disturb' setting on my phone at nighttime so calls are sent automatically to voicemail and the phone doesn't ring yet you don't have to turn your phone off. You can change the settings so that certain people (such as friends and family members) can call you and not be affected.
There's something you can sign up to online so that you don't get cold calls, can't remember the name but it works. I also spoke to my service provider and don't get many (if any) sales calls. I also know if it's a client ringing because I won't have their number saved, so I know when I need to answer professionally.
I think it's a case of each to their own. It helps that I have an online booking system so if you have one you're less likely to get texts and calls anyway. I'm glad I just have one decent phone as I know I wouldn't like having two as it would be pointless for me.
