I still have never had any issues with using spaces in my 7 years, and I think I've tried to pushed many limits! Spaces mean you can use tag names in your graphics instead of having to translate them 
it also means that alarm sources and tags in the chart tag browser for example are more human readable by operators, not that the alarm source should really be displayed to them..
This may be outside of the realm of what you are doing but you could accomplish this much quicker with an hour meter if you have SQL Bridge:
https://docs.inductiveautomation.com/display/DOC81/Hour+and+Event+Meters