Get the 2800+ and spend the extra $100 on more or better RAM. Then increase your FSB by 5 or 6MHz and you'll have a 3000+. Its only an 83MHz speed bump for $100, so no, I'd say it isn't worth the extra money. If you could find a T-bred B for 2800+ for cheaper than both, that might be a consideration as well. They're hard to find, but a 2.25GHz operating frequency might negate any benefits of the increased L2 cache and would be a greater benefit in apps that don't benefit from the additional cache (like multimedia and non-predictable branch apps.)
Chiz