My Grand Financial Plan...Help Please!

[ChromePony]

So I just whipped up a quick excel sheet to approximate this 401k effect without any match and it certainly wasn't very pronounced. I think a lot of this comes from the fact that I'm in the 25% tax bracket now but I'm projecting that I'll be taking 35% out of my 401k when I withdraw it...is this accurate? If so theres about a 2% difference between the two portfolios after 40 years which I think is not enough to convince me to contribute the full amount (until next year when I get matched of course).

I did this with an 8% return assuming my salary stays the same for 40 years (I hope not) compounding monthly. Feel free to poke any holes in my logic, Im going to check the numbers again.