Ya, that'd be a great way to use it.
I don't have many lead acid battery-powered gizmos, but one that I've had for years is an el-cheapo LED spotlight. It has a relatively beefy SLA battery housed in it. It's charge controller sucks (always on), so I have it on a 4 times a year charge routine. Every changing of the seasons...I pull that thing out and charge it up. If you pair it up with the maintenance routine it needs...it'll do its job.
I even took it apart to see what the battery spec was, and made myself a little reminder (the manufacturer actually publishes great specs for their batteries). Manufactured in 2008. I've been religious about topping it up. Still serves me well.