Batterystuff.com recommends the Motocross battery for its price point. Bikebandit.com recommends Shorai and Ballistic Performance lithium iron batteries. Cycleworld.com touts the benefits of the Shorai Lithium Iron Extreme-Rate LFX Battery, saying that its staying power makes the increased price tag worth the investment.
Webbikeworld.com compared Shorai and Ballistic lithium iron batteries with the old lead acid battery style and noted that while the lithium iron batteries are much lighter, the weight advantage doesn't necessarily make up for the high price difference. They also stated that lead acid batteries have a proven track record over time and are much more cost-effective, but that lithium iron batteries last longer and are smaller, which is an advantage due to the space limitations in motorcycle design. Overall, they concluded that they couldn't name a clear winner but that lithium iron batteries may well replace the lead acid style in the future.