They look cool in a pic, but not very ergonomic. Comfort is a factor not easily dismissed, not to mention cost.
Besides, I'd rather have a larger tube
mod with variable voltage or, especially, variable wattage for that kind of price. Perhaps a Texas Select Vapor "Stallion" with a steampunk mod is a better move.
I highly recommend for anyone interested in doing such a mod that they
NOT do it on the battery case itself. Lithium Ion batteries hate extreme heat. Thermal Runaway anyone?