I still think it's better to convert the sounds and aim for making a best of GM bank.
I'm not going to just replace the GM bank with Bandstand as the GM bank already has many sounds better than Bandstand, it's more of a listen and see type exercise.
I'm also going to have other premium content I will want to mix in like Hans Zimmer Guitars and so on.
If I go down the road of making a mega GM bank, then everything will benefit from it without the need to load any additional software.