Yeah there's a lot of camping, especially with the sawn-off shotgun but you can generally work around it if you catch on early enough. I love the retro-lancer, it's more powerful and generally I use it to shoot at still targets because you can get the down before the have a chance to react what with it being so powerful. Otherwise just sprint at them with the gnasher and hope for a 1-shot kill. I love the lance charge as well, much more fun than the chainsaw.
Not had a chance to play this too much lately and I have a busy work schedule ahead so I probably won't get back into it until Tuesday