2006 was the year they started adding the shims, so late 2005/early 2006 might not be shimmed. Yours was
It's a weird gearbox. Mega strong because of the big semi helical gears, but some truly sh1t design and materials choices let it down. Such as brass selector forks secured with roll pins, and no taper bearings on the gear shafts
I have a MK6 gearbox in mine, and I refreshed the gearstick wear parts I could access (the rest have to be replaced after dropping the exhaust and tunnel shield), and it's a very good shift indeed.
It's no MK7+, but it's better than it was with the MK5 gearbox. Mine also felt knackered at the same mileage as yours. The layshaft bearings wear out on them, in as little as 30K miles. It causes a whirring noise when hot, that goes when pressing the clutch pedal. Nothing you can do about that, but it doesn't cause any harm, it's just an irritant.