Considering changing to a gen8 myself, no issues at all with xpenology at all ?
I haven't had any - setup was pretty much identical to my LG nas as far as folders and users / permissions was concerned. i only have plex, download manager for torrents and logitech media server installed (all standard plugins from synology so support is good with regular updates etc) but there are loads more for different apps & functions if you need them, I just don't.
I am using the synology software to run all four disks as a single volume, with single disc failure coverage. With 4 x 3tb installed I get almost 9tb space available for use.
I started with 1 3tb and a couple 1tb disks installed, then as I moved data in I was able to swap out the smaller disks for larger ones. Went smoothly, if a little slow (took a few days) as the volume needs to rebuild after each swap.
It seems rock solid - even sends me emails when anything unusual happens, like after a powercut.
I can't recommend it highly enough really. Especially at the price.