Clubbells: Single or Pairs?

First of all if there is a better place to post this please let me know.

I’ve been looking at getting some clubbells and am wondering if just having one of each weight is fine or if pairs are really necessary. What would I be losing out on if I only had one of each weight.

Instead of the more common ones at rmax I’m looking at the ones in the link below, largely because they’re cheaper and shipping is included in the price for anyone in the lower 48 of the states. They’re bare iron but I plan on just wrapping up the handles with rod tape, that fishermen use to wrap their rods with to improve the grip. I might get the heavier ones from rmax later if I think it’s worth it.
http://www.ironcompany.com/indian-clubs-clubbells.aspx

I’ve used clubbells and each time I only used one at a time.

Except the clubbell swing, I used one in each hand…but now I wonder if I could fit one clubbell between my legs…I dunno.