I agree its no big deal. Running a 1/8" hose and a 18 awg wire are pretty damn close. Personally, I prefer an electric gauge given that there's no oil in my passenger compartment should either the hose, one of the fittings, or the gauge itself happen to spring a leak. Granted, the chances are VERY slim, but it could happen none the less.
The electric gauge is simple my personal choice/preference. No other reason other than that.
