I know a lot of people ask questions on here about this unit and its capabilities and I wanted to give my simple humble opinion haha.
Long story short i found a member over on XRU who was selling his maf cal with the PNP harness, which is awesome and truly PNP. Got it installed in about 10 min and had it up and running, however the guy who sent it had a custom tune done for his truck, which made more power, but was running way too rich for my setup and was destroying mpgs. So I hit up gadget to send me a map that would better fit my setup (afe stage 2 si intake and aero 2525 muffler) so he sent a map made for the gen 1 trd intake (sam as AFE) and his URD catback, which flows a little more than just a muffler swap, but close enough. I've had this map running for the past couple of days and wow what a difference! Truck pulls harder and I've been seeing much better MPG, especially for how much I've been on the gas. It feels even stronger taking the front plug out (AFE Version). Before i left the plug in cuz the resonance of the intake with the plug out when you'd get on it was such an annoying drone, but the maf cal really tones down the volume since its giving the truck the extra fuel it needs to mix with the extra air and create that power.
Also the R4 tuning software is really easy to use if you follow his Utune guide. I have not done any tweeks as i do not have any wideband sensors or tuning tools, but its very easy to view the maps and watch how your truck interacts with the ECU.
Really enjoying it and can't wait for my headers to be on this week!