Should I get an OTS tune, e-tune, or dyno/pro tune for my WRX?

All three are legitimate. The right one depends on how far your car has drifted from a configuration somebody has already mapped. **Off-the-shelf maps** are pre-built for defined hardware combinations - stock, stock plus intake, Stage 2 with specific parts. Free maps ship with the tuning device, and paid VB-specific maps from known tuners run around $150. These are better than their reputation suggests, particularly on the VB. The platform is popular and well understood, and a Stage 1 off-the-shelf map on a stock car delivers roughly 35 wheel horsepower and a large torque gain. For a stock or lightly modified daily driver this is the correct choice, and paying more does not buy you meaningfully more power. The critical rule is that your hardware must actually match the map notes. An off-the-shelf map is written for a specific configuration, and running one on a car that does not match it is where problems start. Read the notes and be honest about what is on your car. **E-tunes** are custom maps built remotely. You record datalogs, send them to the tuner, they revise the map, you flash it and repeat until it is dialled in. Typically $400 to $650, and around $575 for a flex fuel map. This is the sweet spot for most planned street builds. You get a map written for your exact parts, your fuel, your climate and your altitude, without the cost of dyno time. The tradeoff is that it takes several rounds over days or weeks and depends on you recording clean, useful datalogs - if you are unwilling to do that carefully, an e-tune will frustrate both of you. An e-tune becomes the right answer as soon as your combination stops matching any off-the-shelf map, or when you want part-throttle behaviour and drivability tailored rather than generic. **Pro tunes and dyno tunes** put the car on a dyno with the tuner present. Around $400 to $625 for the map on a Cobb-based setup, more for a full session, and this is the tier where you should expect to pay real money on a big build. The advantage is control. The tuner can hold the car at specific load points, make changes and see results immediately, and catch things that never appear in a customer datalog. For an upgraded turbo, an aggressive ethanol build, or anything where the consequences of getting it wrong are expensive, in-person tuning is worth it. The practical decision rule: stock or Stage 1 on pump gas, use an off-the-shelf map. Stage 2, unusual parts combinations, or ethanol on a stock turbo, get an e-tune. Upgraded turbo, upgraded fuel system, or track use, get a pro tune. One caveat that applies to all three: on an automatic VB, confirm the map is SPT-specific rather than a manual map reused. The transmission behaves differently and a tuner who cannot tell you what they changed for it has changed nothing.