Is the output of what you'd normally write to these boot drives significant enough to impact the network? I'm surprised you can't just stream it elsewhere to consolidate the cost.
*Edit -> asked around here's whats up -> we do currently stream some logs/data off the device but we also like it to be written to disk - there's something about having multiple copies that we like ;-)
With an attitude like that, you should consider running a backup as a service company! ;-)