As systemd is  becoming the default init tool on most (all!?) distributions it 
would be very appreciated if you could migrate to it as it would make testing 
new stuff against systemd within a live system (which is at least my preferred 
option instead of breaking my own machines) much easier. Needing to migrate from 
file-rc to systemd just for trying things out asks for additional trouble or 
unreproducible problems. Also systemd should be able to speed up the grml boot, 
so you might want to have it anyway :)