If you have pets or need a hand vac for cleaning uphostery and carpeted stairs, the Hoover BH50030 should be your better choice.
Hoover BH50015 vs BH50030 Compare 
images from manufacturer
The Hoover BH50030 is a pet version, it comes with a Motorized Brushroll which is for picking up pet hair and cleaning carpeted stairs, Pet Upholstery Tool which is designed for grabbing pet hair on upholstery, Deluxe Dusting Brush for cleaning delicate surfaces, and combination crevice tool/dusting brush; whereas the Hoover BH50015 only includes a combination crevice tool/dusting brush. Many users complained that this tool did not stay locked into position.
Both of these two hoover linx cordless hand vacuum cleaners:
are bagless;
have clear plastic dirt cup;
powered by interchangeable 18 Volt Lithium Ion battery;
have Battery Fuel Gauge that shows remaining battery life;
priced at $129.99 at hoover.com;
carry a limited 6 year warranty on vacuum, and limited 2 year warranty on charger and battery.
Not sure which of the two hoover vac cleaners to purchase,50030 or 50015. want mainly to clean car.
BH50030 works great in the car or RV, it keeps its charge long enough to do the cleaning job.