I have an Inovatronix Tronix Explorer that I have had since 2007. I had to replace the gel cell battery in 2014. The new battery cost me $38 at Batteries Plus. I found a YouTube video that showed me how to replace the battery myself, and it was a fairly easy procedure. The Explorer is somewhat large, and it is not a lightweight unit, coming in at 18 pounds. It has two AC outlets. I use it mostly in a small, 2-wheeled hand truck type deal, in an oversized crate, using the weight as ballast and power for a small 200-, or 400 Watt-second power pack, so for me the weight is not a problem, and is in a way, an advantage: the 400 weighs 12 pounds, so I have 30 pounds of ballast. On the handtruck's handle, I have a 9-foot light stand, so I have a rolling light and 30 pounds of ballast. I do envy the small size and light weight of the Vagabonds though. It WILL power my big 1600 and 2400 W-s power packs, but it's very slow to fill the capacitors on the 2400--but it CAN do it!