Hi there BikerBob. Just getting to grips with my GLA 45 AMG (almost identical to yours - dark grey without the AMG rear spoiler) and looking at options for bike carriers. I have a Thule Raceway 992 (3 bikes) and there's no way that beast is going to fit onto the rear hatch. Too heavy and the retaining claws are too narrow, as well as the cables sit unprotected on edge of spoiler - nasty! No way i can retrofit 'hatch huggers' either. I was assuming the only way was Thule roof bars (Aeroblade Edge 9594B)... until i saw your post showing the Saris Bones 3 on the rear hatch with Saris hatch hugger straps.
Can i check a few things with you please before i purchase:
1. The plastic rear hatch outer skin sections, that overshoot the metal hatch, look a bit flimsy and thin to me. Have you had any issues with cracking or damage using the Saris rack?
2. You mentioned that the hatch hugger straps still allows the rear hatch to open and closes automatically. I'd assumed you'd have to slide the carrier on and off with the hatch is closed? Does it stay tight in place when opened (assume this is once bikes removed)?
3. What load can it take (3 adult mountain bikes)? I've got 3 Trek hybrids.
Thanks in advance for any advise you can give.
I think my next posts on the forum will be on tyre pressure tests, MPG, and fitting a Snooper radar detector.
Still not stopped smiling when i hear that AMG Valvetronic exhaust popping.... ;-))