I have used PyTorch Lightning. (While I can’t compare the two, as I haven’t used Ignite).
It has been the smoothest experience as far as I have come across, w.r.t multi-GPU training. Changing from a single GPU to a multi-GPU setup is as simple as setting num_gpus in trainer.fit() to as many as you’d like to use.
TPU support is also integrated, where you’d just specify num_tpu_cores, without changing any code.