The RockNRoller will be my third 'cart' for carrying equipment in and out of gigs. The first was a very clever fold-completely-flat upright aluminium trolley type, which was extremely light, folded up very small, and could carry quite a heavy load in terms of weight, but couldn't carry much 'bulk' as the load plate was quite small. Not recommended. The second is similar, steel, and better shaped to take larger bass-bins or heavy items that don't have castors. I still use that one for shifting larger single items around (bass bins etc.), but that's it's limit for me.
The need for the RockNRoller cart arose from playing in a new two-piece pub and club band. I was fairly content physically carrying my equipment in and out, but one of the more important venues objected to us travelling through the crowd so many times carrying just a few things at a time, citing public safety as their concern.
The RockNRoller allows me to empty a pair of 450w speakers, small guitar amp (Cube), monitor, various cable boxes, racks, drum machine box, speaker pole/mic-stand bag and a couple of guitars (in hard-cases) out of the car and onto the cart in one go. With the other guitar and laptop gig-bags slung over the shoulder, the get-in is reduced to just one trip through the crowd to the back of the club, and the same on the way out. Getting through a crowded pub is easier, as people part out of the way when they see the loaded cart coming. Needless to say, the RockNRoller is now used on every gig possible.
The cart is quite heavily built, taking up slightly more room in the estate car than my other cart, but more than makes up for it by being able to carry so much equipment in one go. This model, when extended to it's full length is about the same length as the case for my bass, but there are longer and shorter models to choose from in the range. Expanding or collapsing to and from it's fully folded condition takes about 15 seconds.
One other lesser-known point I'd like to make: I haven't had very much equipment stolen over the years, but when I have, it was something that was either in the club while I was at the car, or something in the car, while I was getting gear from the club. I am less worried about security now, as everything is in sight at all times.
I would highly recommend it for the car or van based small band or DJ setup for carrying many items in one go. Although it could still have use in a setup where larger bins, tops racks etc. are being moved around, I find my upright cart easier to use for this purpose.