Well you can't smack them...you could try but it wouldn't really be effective. I use more yeast nutrient then with the smack packs because the little pouch in those has nutrient in them. I normally use smack packs just because I can get them fresher (last time at the lhbs freshest white labs tube was 4 months past it's best by...)
I use white labs for most of my brews and it works great. I'm sure everything else works just as good but WLP is what everyone carries and my LHBS carries it for liquid strains. I haven't done any lagers yet, but it works great whether you add a starter or not. If you get it and it looks clumped at the bottom, just let it warm up and shake it around. It might be in either fine yeast particles or something that looks like tapioca pudding. Either way just let it warm a bit and shake it up. Also, be careful when opening. They tend to build up pressure and spray a bit when opened. I just open it in my sink over the cup I use for starters.