I would get them both. If you're in the states, your town probably has a Craigslist, which is like an online flea market. These days, people are selling all kinds of great things, sometimes in great condition, in a bundle and at dirt cheap prices. I just got a DSi for $55 and a DS Lite for $40, almost new, barely played, cause the guy selling them was short on rent... His loss, my gain...
And with an new R4 card or two, you will be so busy with your new toy, that you won't even notice when the 3DS becomes "old hat"... haha
Oh dear, i just realized how old the post is, how is the past back there? The future's so bright, you gotta wear shades...