I'm pretty certain coasting in 5th gear at 1000rpm is absolutely fine for the car/tranny/clutch/engine etc.... It doesn't lug, it's not a problem. I think if you are not running your VX below 1400RPM you are not tapping the potential of the car. Sure I'm a noob to it, but still, 1400rpm is high for this car. I shift at 1400rpm.
I'd say coast in neutral unless you need to slow down. Being in 5th will slow you down if it is in fuel cut mode (above roughly 1200rpm). If you are at 1000rpm, it should go farther in 5th, but it will be injecting a bit (probably more than idle) of fuel to do so.
thats my guess.