DiskStation DS420+

i ran into this with my ds420+. synology is super picky about ram. ecc sticks usually just won't boot or throw errors. you're better off getting a non-ecc crucial or timetec module - they're cheap and work. i grabbed Crucial 4GB DDR4 for mine and it's been solid for two years.

I'm running it on Synology DS420+ +8GB RAM, which is on a terrible hardware (Celeron J4025), but I'm out sourcing most of initial import tasks to my Linux laptop (running microservices on my laptop with mounted volume through Rclone. this is advanced usage, don't try this unless you're experts)

As ppl have said already, it depends on if your playback device supports the codecs used in the media for direct playback (no transcoding), or if you'll have enough bandwidth in the network to even do direct playback, or if you'll transcode it in case some codecs are unsupported. the Synology Beesta

I'm afraid i dont know pricing in your market, so cannot make too many recommendations. £180 for a good nas unit probably limits you to used or refurbished units. If you can find one used or in inventory, a DS723+ or DS423+ are great units. The DS720+ and DS420+ are still in support and good units a