I'm sure the PIMP is a great product, I've known the designer Wes Kiser for many years now and he's a great guy, super sharp, and we have alot of respect for one another. Assassin is correct they purchase the uS Modules through B&G directly and not through us so we don't see a dime from PIMP ECU sales.
To clear up the misinformation for thru-hole versus SMD, while it's true our DIYPNP units use through-hole components so the home assembler can solder them up easily-- the MSPNP Gen2's use surface mount components however. In reality that's more about mass-manufacturing and has a very small effect on durability, though there is some small benefit to SMD. We do it for that reason and also to maximize efficiency in manufacturing. It doesn't always cost less, but it's easier and consistent.
As for low versus high impedance injectors I'm not sure what the PIMP uses, (VND's I think?) though I can speak to the MSPNP Gen2 which uses true Peak-N-Hold circuitry to peak open the injectors at 4 amps, and hold them at 1 amp to prevent overheating the injectors. Peak-N-Hold capability also maximizes injector performance by minimizing injector opening/dead times as compared to some of the other methods we could have chosen to use.
We considered using VND's which we do use on some other products, but have found that while they work very well for high impedance injectors, and can in some limited cases work with low-z injectors, they don't work well for low impedance injectors in many cases. The problem is that they max out at 5amps and current limit which causes heat to be generated, a little heat can be dissipated through a well designed heatsink- but many low-z injectors will generate a LOT of heat in this circuit and can cause problems. Based on ohm's law (google an ohm's law calculator, it's easy to do this math) they 'should' work fine for an injector that's 2.7 ohms or higher assuming 13.2v in the charging system. Anything under 2.7 ohms will try to drive the transistor harder than 5amps which will current limit the transistor and begin to generate heat, and if they get hot enough they will not function properly, usually after the car is nice and warm and you're in the middle of a dyno session or race and seem to have an 'intermittent problem' that doesn't occur when the car is cold, which makes sense as it takes a few minutes to overheat the VNDs and start causing the problem.
We had this happen recently on a customer's Miata that was using a DIYPNP (which uses VND's) and prepping for the SOLO Nationals, they were having problems when tuning that was causing the injectors to drop out, they thought it was an ignition problem, but when we heard what injectors they were using we determined they were simply using the wrong ECU for the injectors they had. (They could have used a resistor pack or external PnH box to solve the problem). As time was tight, we got them setup with an MSPNP Gen2 for their car and the internal PnH circuit immediately solved their problem.
The MSPNP Gen2 also has a very slick analog knock control circuit that's tunable. It's not as slick as the digital knock circuit we've got available for MS3 now, but it works in much the same way just using analog circuitry to do so giving you the noise floor and knock frequency tuning without the windowing capability MS3 has. It also has a headphone jack allowing you to listen to the knock sensor when tuning using it as a set of detcans, which can be helpful when tuning. (knock sounds like a scratching or static-like noise when listening with detcans like this).