Work Life balance, reality or impossible?

I was having a conversation with one of our partners this week around Work life Balance and, knowing I was due to go on holiday soon, she asked me “do you work when you’re away or do you take a complete break?”
That questions then led to a long conversation about how I work, what hours I do and how that affected the service we, as a company, give to our clients. Firstly, I think it is important to note that one area our clients always compliment us on is our service levels, so I don’t think service is an issue. Secondly, I try to provide our services across the Thames Valley, specifically Bucks, Berks and Oxon, so it is easier for us to deliver face to face as well as remote support. Lastly, I have never been afraid of hard work and have always instilled this as a value throughout our team.
So, how do I work, the simple answer is when and where I need to. We are a virtual business, we all work remotely and have great technology to support this. Typically my day starts at 5.30 when I do an hour’s work before training for an hour or so (my obsessive gene). This means I am ready to have breakfast with the family before my son leaves for school at 8.00 and I start work again. I will then have a break around 4.00 when my son comes home and if I need to will start work again once we have all had dinner. Obviously if I am at meetings or on calls this changes, but ultimately I can work when I want and need to. The pros are immense, not least, I can take an hour out if I need or want to, to go for a walk, ride, swim or just watch the Tour de France. The main con is that I usually do a minimum of 50 hours a week.
So, going back to the question I was asked, “Do I work on holiday?” The simple answer is yes, in that twice a day I check emails, delete the junk, forward ones that need actioning, the normal in this day and age. However, unless there is a specific project or issue that I know about and have planned, I don’t do any work. I have long realised that life goes on without me and whilst I would love to think that I am invaluable to clients, I am a realist. I also plan ahead and make sure everything is covered whilst I’m away.
Holidays are there for a reason, to give you a break, no one can work at full pace without resting, if they do the quality of work and their productivity decreases. Having worked with and for a number of large corporates who think that just because they pay good salaries, they have a right to expect staff to work all hours, even on holiday, I know this is not the case. These businesses end up with decreased productivity, reduced revenue and losing key staff sooner than they should, this then costs money, not just in lost income but in recruiting, re-training and lost clients. Someone should tell them that staff with a good work life balance deliver better results!
So for me, I won’t be taking calls, or working on projects, if I had to that would suggest that I am not very good at time management and planning, something I work with a lot of companies improving.
What do you do?