Do you have WIFI at home? If so, you don't need the cellular data connection at home, nor would you want to use it. I use the cheaper $15 250MB plan and make sure I have access to the faster WIFI connections most places I go and just use the 3G when on the road. If I wind up using more, it just adds another $15. Which is what I would be paying every month anyway. So far, I have not gone over.
If you only use your iPad at home with WIFI, you don't need a plan at all.
While you're here, how would the thing work doing something that used a command line interface? The idea of using it for remote access to work is kind of attractive, but I've been moving away from GUI management utilities toward CLI and Powershell.
[Raises hand.] Yep, that's me.
Well, I might end up at least looking at one in the coming weeks. My trusty old 1st-gen iPod Touch lost its mind yesterday, and it doesn't want to come back. I suspect either the battery has gone south or the charging circuit died. So being a tinkerer, I'm having the "repair vs. replace" conversation with myself, and the thought emerges, why not an iPad, since shirt-pocket portability is not an issue -- I use the thing only at home, for music, reading, and entertainment, and the iPod screen is too small for some things I'd like to do with it. So maybe an iPad makes more sense.
I'll check back in a few days and let you know what I'm thinking... too soon to tell. I'm still reading the "How to disassemble your 1st Gen iPod Touch" pages on the interwebs... doesn't look too bad. Although tonight I'm feeling lazy. Good thing the stores are closed. (No, don't tell me to order it over the net, la-la-la-la-la-la-la). I gotta think about it... ;-)