Let's look at the main factors before trying to answer that:
How quickly will the equipment/firmware need updating to remain competitive?
How quickly will the equipment/firmware become obsolete?
Where is consumer resistance the bigger problem to overcome, on outright purchase or on "rental"?
As the client: If there is no real need to update I'd be resistant to ongoing fees - unless this made initial purchase more affordable.
I'd take a very close look at it from the client's point of view before making any decisions. I'm sure I'm missing angles, but perhaps a starting point.
Did you like this article? Share it with your favourite social network.