We have nothing against Bosch or Yamaha but let's admit it, their background is fridges and synthesizers. Both entered the e-assist market advertising power and battery life, but there's more to an e-assist than that, especially if we're talking performance.

A Bullitt takes the challenge of urban gridlock seriously In gridlock a bike accelerates and decelerates at a moments notice. It dives into corners and modulates speed. The perfect e-assist is one that is tuned to the rider. And that's where Shimano, the only name in bicycle parts holds the philosophers stone. The E6100 has competitive power and battery life, but if any bike can read you mind, it's a Bullitt. And if any motor can, it's Shimano.

Most cargo bikes split apart in the middle for flat packing. That's fine for most cargo bikes, but the Bullitt is made for abuse. It's one-piece welded frame is made of oversize, squared-off aircraft aluminum tubes that won't flex a millimetre in tight corners. Oh, and it's aluminum, so it will also never rust.

That means a strong frame with a responsive feel, that keeps you in one piece, even if you're hopping curbs and dodging potholes - whether intentionally or just because they're there.

At only 46cm wide, the Bullitt frame is the product of street smart design. Stiff, lightweight, narrow and tough. Nothing pieced together here.

The Bullitt is a one-size fits most frame solution. How do they do this?

First, the top tube of the bike slopes generously. We've seen riders 5'4" hop on easily. Second, the bottom bracket sits very low to the ground. This means even shorter riders have a toe on terra firma. It also makes the bike handle better too. Third, all Bullitt's come with the Satori Easy-Up, a clever device (pictured) that raises the handlebars up and down with the flick of the lever.

Why no step through frame? We are asked this a lot. A step through is less strong and super flexy. That goes against the Bullitt DNA.

Your E6100 comes in two options, and the choice is difficult!

The first: A Nexus 5 internal hub. Very low maintenance and the only internal gear hub designed for e-assist. This is connected to a Gates belt drive. This can run for 30,000km without replacement. Plus electric shifting! However, range is limited and you'll often rely on the e-assist power levels as your 'gears.' For the practicalists.

The second. A wide range Shimano XT system with a huge 11-42 cassette. Also, electric shifting! This is higher maintenance but you'll always find a gear, so you can keep the assist humming on low, preserve battery life, and keep those legs pumping. For the purists.

Carrying heavy stuff in a cargo bike means you need the most intuitive and powerful brakes possible. The Bullitt uses big 203mm hydraulic disc brakes, the same kind used on high performance downhill mountain biking. That may sound intense, but what it really means is lots of power, and near-perfect control.

Bullitt bikes use four-piston hydraulic callipers. What does this mean? Most bikes use two-piston callipers. These will stop on a dime, but a Bullitt requires more precision handling, especially with the added velocity of 100kg cargo loads.

The four-pistons brakes are light to the touch and intuitively modulate motion and arrest motion. If you want highly responsive brakes that can read your mind, these are it.

These brakes aren't just meant to stop, they're meant to control speed, especially in corners and high contingency situations where you need to stop, suddenly.

Who are those white haired people ogling the DHL cyclist? Why, that's the writers Mom and Dad (partner-in-crime and longtime Curbsider Aaron in baseball cap ogles besides).

Like Babboe who supply TNT and PostNL, Nihola who supply Dansk Post, and Urban Arrow who supply UPS, Bullitt is also deep in the last-mile logistics game. Why is this important? Because commercial use is an empirical indicator of a products consumer-use durability. Unlike Babboe, Nihola, et al, Bullits were purchased by DHL to be fast. That means more curbs, more rider force, and generally, more strain.

A Bullitt bike is whatever you want it to be. While you can only choose one colour, it can change its colour quickly, to use a metaphor.

Need to carry stuff? Grab the Cargo pack. The cargo pack uses impact-resistant honeycomb boards, strong and light (using the same stress-skin and space-frame as aircraft construction).

Want to carry kids? Insert the foldable seat (which folds up to make lots of room for groceries), and install the canopy. Canopy is not the right word. It's an impact resistant, full-coverage roll-bar with a waterproof cordura cover that rolls up for sunny days.