The THS looks good, performs well but tbh THS arent exactly a massive intercooler company. They dont offer a huge amount of intercoolers as such have a huge amount of experience. They also have a go at engine mounts, exhausts etc. Do they develop their own cores in house, or are they bought in? Alot of companies dont make their own.
Yet Pro alloy are a a much larger producer of intercoolers on a whole variety of cars and pretty much only deal with alloy radiators and intercoolers. All cores etc developed in house.
When Pace products fitted my intercooler/rad kit they said they had just developed their intercooler kit for the Mk5 and S3. Might be another option to consider. Again another company who develop every big in house.
Id be looking at pro alloy in your shoes tbh,