Let me talk to you....
I was in your position. I got a BSEE and I had just under 2 years worth of internship experience under my belt. The first job i was offered, it was a temp to full time position. I said no. It Paid $21/hr, which is what was less than my last internship. The 2nd job offer, it was for 50K. I said no because I thought I was worth more. Then I decided to jump to consulting. The money was supposed to be great. they gave me 58K plus yearly bonuses and they hyped it as if i would get big raises. It ended up being 60K a year after bonuses...and this was after 9 months of looking after graduation. Then, the economy got worse...they freezed wages and cut 3k off my pay and took away lots of my bonus.
Well....now I make $0/hr b/c I got laid off. I look back and wished that I took that temp to full time position. I want to go back to doing what I did, but when people see my last three years, they just go, "well, your last three years has nothing to do with this position". It's an uphill battle that I have been battling for the past 2 years (I started looking well before I got laid off).
The lesson...don't go chasing after money when you really do not have the know how to back it up. I mean, if they offered you 30K, I'd say screw it. They are offering you 42K, which should be good enough. As a new grad, you are a dime a dozen.