I was really happy to see this come up on Tindie. It takes a routine battery discharge test I have to regularly perform go from a time consuming manual operation to an easy hands off task. Will be buying several more to build up a discharge rack. I does have a couple of quirks that have been getting addressed in firmware updates but the documentation isn't keeping up with the changes so you have to dig a bit. The command to enter an under-voltage set-point that was not in the manual. Look forward to the fan upgrade to get a bit more wattage.
When it came time to test my own Pi Power product, I went to the electronic store and bought a selection of 10 watt resistors. I quickly discovered that they're frankly not very precise, and switching them in and out - particularly after they've spent a half an hour dissipating 10 watts and are ROCKET HOT - is fairly inconvenient, not to mention not terribly flexible.
So I bought a 6 amp ReLoad. It took some time for it to ship, but not an inordinate amount (I'm not counting the transatlantic transit time - just the time it took between ordering and shipping).
I chose to assemble it the simplest way - bolting the transistor (if that's what it is) to its heatsink and soldering it onto the board. This could have been regarded as a tactical error - when that heatsink starts to get hot, the adjustment pot is a bit too close for comfort.
I made use of the option to measure the current via the voltmeter connection on the side of the board. I didn't attempt to calibrate it precisely, but out-of-the-box it's accuracy was adequate for my purposes (within a few dozen mA so far as I can tell).
I did notice after buying my ReLoad that the seller has a "pro" model in a case with a display. The lack of a provision for a display is one comment I was prepared to make in my review before I discovered this. Since I already have the unit in hand, and because I'm handy, I may cobble together a little throwaway voltmeter dedicated to being the current display for my unit. It won't be as pretty as the pro version, but it'll fit right into what my bench looks like most of the time.
The only other thing I might nitpick about is that I might have chosen a multi-turn pot to make dialing precise values easier (particularly when you're trying to be precise without burning yourself on the heatsink), but, of course, there's nothing preventing one from going out and buying your *own* multi-turn pot and making the switch.
But on the whole, the value is the most compelling argument in favor of the ReLoad. It's a great deal on a very, very helpful piece of gear.