Which carrier are you going with? I'm not enamored with the price of Verizon's Plan, AT&T at least has a lower price option, but I'm kinda tired of AT&T's spotty coverage, I've had my Phone and Ipad 1 on them before, that I want to give Verizon a go.
If carriers were offering family data plans (buy 5GB per month and use as you please among various devices), then I would strongly consider buying a unit with 3G/LTE. At the current offering, I just can't justify buying yet another stand-alone data plan.
You aren't buying a data plan, you're buying the option to purchase data as-needed.
I understand that, but the two are absolutely related. If I don't want/can't afford the data plan, then there is no point in purchasing a model at a premium that includes 3G/LTE functionality.