The SD9VE is a very reliable pistol, IMO. While any make or model of pistol can have a lemon, in general the SD9VE doesn't seem to have many issues, and isn't known to be ammo sensitive. I also think the Shield 9mm is a great gun.
The Shield will probably cost about $150 (+/-) more than the SD9VE. The SD9VE has a greater capacity: 16 versus 7/8 for the Shield 9mm. The SD9VE is a bit bigger than the Shield, but many people carry them and it's similar size gun, the Glock 19. The trigger on the SD9VE has a heavier pull weight than on the Shield, but the Shield has an external safety...which some like and some don't. S&W has announced a new Shield model without a safety.
IMO, for an all-around gun for home defense, carry, and range fun, the SD9VE is hard to beat. With the savings on purchase price, you can buy ammo. On the other hand, if you are looking primarily for a CCW, the Shield is a good choice since it is smaller, and the capacity isn't really an issue in most civilian self-defense situations, where the average rounds expended is 2. Even though you pay more for the Shield going in, in a while you won't remember the price difference...it's not that much.
Either one is a good choice...it's primarily going to depend on which one best meets your needs and budget.