Just starting my upgrade journey on 20 plate mk8 and have ordered the m235 from Mountune. Unfortunately I've had problems with delivery. Complained to their customer service and the reply so far has been unimpressive.

Does anyone have experience with Mountune? Or am I better off with someone like Superchips?

mountune are very good, but when there stuff is out of stock prepare to wait months, as a side note they like to discontinue stuff, i wouldn't go superchips, stick with mountune, however i would look into revo, Collins and dream science,

with regards to superchips they are still living in the 90s and there is a reason they went under and then got bought out.

have you considered a custom map