Subframe cracking

Hi there
Can anybody tell if cracks in the rear subframe are frecuent?
I have a 2002 Steptronic MGF and I love it. I’ve also converted its hydragas system to the conventional one and it is a lovely car to ride.

What kit did you use to update from Hydrolastic?
If it was using the original subframe but something like the Suplex kit then it is known that can crack the top mounts without strengthening.
If you changed to TF subframes then I haven't personally heard of any major subframe issues other than rust.

Thanks for your answer, I don't know the replacement part brand, but the cracks were produced during the hydrolastic phase.
My question was oriented to get to known it subframe cracks were a common failure on the hydragas system. I believe mostly due to hard-driving .

The only time I have heard of subframe cracking was with Suplex conversions on hydrolastic subframes, I have never heard of it with standard suspension for either MGF or TF.

The only circumstances that I could imagine cracks forming with hydragas spheres is if they have lost all their nitrogen gas and have been pumped overfull with fluid to try and compensate for the low ride height.
This would give no suspension travel or compliance and transfer all the shock loads direct to the mountings.
In such a scenario the thing would be so uncomfortable as to make the car undrivable on any surface less smooth than a tournament billiard table.

Thanks for your answer, this may explain this failure, as when I bought the car cracks were already there and the hydragas system was wreaked.
That's why I decided to switch to the conventional system. Although the subframe remains resented.
Hope this time the welding will resist.