Neither one fits. I've had a shop try to install the Curt, and while the holes and everything line up, the hitch prevents the exhaust tips from being put back in. Shop contacted Curt and asked if something was wrong and (at the time) Curt didn't know there were differences between the AMG and non-AMG fits. This was before Curt/Draw-Tite specified that it would fit the 250 model because the site only listed that it would fit the '21 GLA. Shop owner showed me the problem and we both agreed that the Draw-Tite would run into the same issues. Been looking for a hitch since. Decided to go with a roof rack bike rack since it seems like it might be a while before something comes out.
StealthHitch was working on a hitch for the '21 GLA but last update from them was that production was on hold due to material issues.
Edit : Yes you will need to cut the heat shield and make a slight cut into the rear diffuser to make them fit. They ended up cutting my heat shield, but not the diffuser since they noticed the exhaust issue before cutting into that. But I believe that any hitch in the future will need these cuts made regardless.
StealthHitch was working on a hitch for the '21 GLA but last update from them was that production was on hold due to material issues.
Edit : Yes you will need to cut the heat shield and make a slight cut into the rear diffuser to make them fit. They ended up cutting my heat shield, but not the diffuser since they noticed the exhaust issue before cutting into that. But I believe that any hitch in the future will need these cuts made regardless.