I bought a plastic Case Guard MTM Front Rifle Rest because someone recommended it to me, but I never liked it. They liked it because it was easy to leave in the trunk all the time, to assist new shooters to sight in their rifles.
hxxp://www.basspro.com/MTM-Front-Rifle-Shooting-Rest-Model-FRR30/product/95062/-1397826
I also bought a bunch of Protektor leather sand filled rests because I'd read they were the best and most resembled what I'd learned on, but I didn't enjoy them either.
What I'm currently using are these cheap sand filled rests
hxxp://www.basspro.com/RedHead®-2Bag-Shooting-Bag-Combo/product/81311/-1275348
and filled it with Home Depot dry play sand. They work very well with my
BTVS.
I also bought this big one
hxxp://www.basspro.com/RedHead®-Bench-Shooting-Bag/product/81313/-1275349
but combined with everything else I carry to the range it just becomes too heavy to lug around.
There are of course much more expensive options, really designed for much longer shots with heavier calibers.