What's a VESC?
There's a lot of scattered knowledge about VESCs available online, but I'll try to summarize the important details. For starters, to understand a VESC, you need to know what a controller and a BMS are. The controller, or ESC (Electronic Speed Controller), is a piece of electronic hardware in every electric vehicle that controls the power delivered from the battery to the motor. Battery safety is controlled by the BMS (Battery Management System). In most one-wheeled electric balance boards, commonly referred to as onewheels, the controller is in the front of the board and the battery pack and BMS in the rear.
VESC refers to an open source hardware and software reference design for motor control developed by Swedish genius Benjamin Vedder. VESC stands for Vedder Electronic Speed Controller. Many different companies manufacture VESC-compatible ESCs for everything from motorcycles to RC airplanes. If you put a VESC in a balance board, then it will work with a wide range of batteries and other upgrades. There are several VESCs made specifically for balance boards, but the first one to become widely-used for this application was the Little FOCer, sold by MakersPEV. In addition to broader compatibility with batteries and other upgrades, a VESC also adds cool features and fine-tuning options. Swapping the stock Future Motion Onewheel controller for a VESC will yield more torque from the existing battery because the FM hardware limits how much battery current can pass through to the motor, decreasing available torque to get you up steep hills and over obstacles. VESC is a registered trademark of Benjamin Vedder.
Older Onewheels were easy to repair or upgrade by swapping parts. Now, the controllers in the front of all new Onewheels are paired with the BMS in the rear, so the board won't work if you swap parts from an identical model, let alone try to install an upgraded part. This pairing scheme was implemented by Future Motion in an attempt to prevent unauthorized repairs and upgrades outside their factory in San Jose, where you have to ship your entire board for any warranty repairs. After arguing without evidence that allowing users to repair their own Onewheels would be dangerous for the previous ten years, FM did start selling repair parts in 2024 when compelled to do so by California's new Right to Repair law. Very smart people have figured out how to re-pair Controller and BMS in many cases, but it's an arms race with FM, and a needless pain that leads many people to just pay FM for a $600 repair when something breaks, or simply buy a new board (i.e. planned obsolescence). I won't get into the details, but controller pairing is one of the many reasons that FM is widely-regarded as an anti-repair, anti-consumer company.
You'll probably be happy on a stock Onewheel for a long time, but someday you might get into customizing the footpads, tires, rails, etc., and maybe your controller or BMS broke, or you might want more power and more features than a stock controller can offer (except perhaps a stock Funwheel or Floatwheel, which contain VESCs). Replacing the stock controller in a Onewheel with a VESC opens up endless possibilities.
While Future Motion's patents prevent other companies from selling competing products to the Onewheel, they do not prevent the sale of repair parts and DIY kits. Patents last for 20 years. Until Future Motion's patents expire, there won't be much competition from pre-built VESCs in the USA, so the best way to get a better one-wheeled balance board is to build it yourself or have an experienced builder help you out. The hardware takes some time and money to collect, with the most expensive part being the battery pack ($600-$1,000, unless you make your own). You can also reuse a working XR BMS and battery pack, including a CBXR or JWXR extended battery pack, and still see improvements with a VESC controller.
Aside from needing basic DIY skills and the ability to follow instructions, the biggest difficulty in building a VESC is finding parts in stock due to high demand. If you get a used onewheel like an XR and bide your time, you can collect parts while you learn on a really cool, stabile, lightweight platform. Then, by the time you've collected everything you need, you'll be ready for something way better than any new FM board, for less money, something that you can repair and upgrade down the road as you wish.
There are lots of strongly-held opinions on which board is best. Very few of those opinions specify how, where, or with whom the person rides, how much they weigh, shoe size, other vehicles ridden, technical aptitude, or myriad other factors that determine what board best meets the needs of the individual. A conversation with one of our builders may help you decide what's best for you.
Don't make the same mistake I did and wait seven years to get a Onewheel. The biggest mistake I made in getting myself a Onewheel was not getting one sooner. Find a local used board, and if it's not for you, you can sell it for what you paid. Don't waste your time or money saving for a new board that will get scratched and beat up in the course of learning to ride. Get a used one as soon as you can.