Mixed random & ordered partitioning?

[Todd Fast]

I want to do ranged row queries for a few of my column families, but 
best practice seems to be to use the random partitioner. Splitting my 
column families between two clusters (one random, one ordered) seems 
like a pretty expensive compromise.

Instead, I'm thinking of using the order-preserving partitioner in my 
cluster, but distributing load for most of my column families by hashing 
the row keys in my application code. Then, for the few column families 
which I need to slice rows, I can just use unhashed keys.

What is be the effective difference between hashing the keys myself and 
letting the random partitioner do it? Is this advisable?

Thanks,
Todd