I think cory is spot on - focusing on asylum seekers isn't going to give you a picture of the true immigration landscape so again can be misleading in terms of the wider debate (and also what can, legally, be done if people feel there is a problem.)
And Spero, with due respect to your experiences I'm wary of anectode as I'm unconvinced that an individual's case load is even a true representation of the full picture of asylum seekers, let alone immigrants, and I'm wary of conflating the two.
I'm an immigrant - white other, living in London. My son is one of those pesky children born to a mother born outside the UK. The fact that his father is British-born is apparently immaterial. I'm fairly literate, I pay my share of taxes and I like to think have a decent moral code.
It might like to help dinky, in making comments about how most immigrants are amoral and illiterate due to the strife-torn countries they left, to actually read the Census and learn where the majority of recent migrants have come from.