The down side with that route is that it can hinder bipod use in certain cases and angles.
Since the connectors are external, I would recommend using a barbed fitting and clamp rather than your standard push connect. Push connect fittings are annoying sometimes because if the tube is pushed too far in one direction, the o ring seal opens a little allowing for leaks... (massive leaks). When the CO2 is situated inside the stock, the stock housing keeps the tubing in place to prevent this, but since you want it outside, you should stick to barbs.
I personally think barb fittings hold the tube better, since the friction fit is much stronger than the push connect's barb hold. You can also get barb fitting to QD fittings from McMaster, this makes things easy.
The upside is that the regulator is always pointing up when firing straight, so the chances of liquid CO2 events are diminished.