get real!
for comparable but worse device (windows ce tablet h/pc PA-2400, 80Mhz SH3, 480x240) Casio charge you $800.
here for $520 you get better device + 1 year free internet (worth of $10/mo, check other plans and try plaing with numbers) => device only comes to you for $400. what a steal, huh?
you may consider the 3-year plan... there is a good chance they'd go off bussiness till then and you'll keep your device, you can connect to any isp, upgrade winCE... whatever.