Getting dump of vbucket for seeding new cluster (or restoring old one)

I am using membase 1.7.1 server cluster of 3 machines (vbuckets only), and would like to be able to back up the contents for the case that the entire cluster goes down, or to seed a new cluster.

I periodically get new data from my provider; I want to keep the old data around more or less indefinitely, and add the new data. Imagine a wine rating application. New vintages come in all the time, but I need to keep the old ones around.

Currently I have a process which does the following:

Download some data from 3rd party provider
Push data into my vbucket; some old data may be overwritten, some data will be new
Hang out until next data update; other processes will be reading the data

What I'd like to do is:

1 See if my bucket has any data in it
2 If it doesn't, load from offline storage (see step #5)
3 Download some data from 3rd party provider
4 Push data into my vbucket; some old data may be overwritten, some data will be new
5 Take dump of all data into offline storage
6 Hang out until next data update; other processes will be reading the data

Steps 1,2, 5 are new.

So the question is about step #5. Is TAP protocol a good way to dump out the contents of my membase bucket? Will it interfere with readers?

Perhaps there's another way to do this which I'm missing?

Thanks!