Primer on SSD and internal hard drives

If your streamer has a buffer in it, there won’t be any noticeable difference. If your streamer doesn’t have a buffer, then definitely get the SSD. But most likely your streamer has 4 gig of memory and you’ll be fine with either. Oh, one more reason to use SSD memory it the chance of it dying is very small so losing your library is very small.

All the best.

A more common issue is size constraints.My first streamer did not support any greater than a 1/2 Tb SSD.

All memory could go at any time. When your PC freezes it's a warning

For warranty they make you send it on your dime and then it's gone forever. I. hane been stiffed by more than one mftr.

Whoa, a topic with general consensus! That never happens here. OK,  Spinning disks are the past. SSDs are the future. No moving parts so less power, less heat, longer life, and absolutely no SQ difference. 

Spinning disks deserve a special place in history for helping put the modern world online. The original iPod used a postage stamp sized Toshiba 4GB spinning disk that was the pinnacle of technology 20 years ago. Today I keep my iPod full of 160 and 320K MP3s as a reminder of how fast technology moves. My current phone has 256GB of SSD full of uncompressed FLAC files.  

SSDs' are quicker, zero moving parts, and less power draw.  As time goes by, even the larger drives' prices continue to edge down.  Smaller than a SATA as well.

Considering swapping all drives over to SSD, but don't forget to max out your RAM.

Spouse just punched her desktop up and the change was immediately noticed.

Shop around like you do for your 'anything else'... ;)

To answer your specific questions:

So what is the difference between an internal hard drive and an SSD?  Is one preferable? ----- SSD can be external or internal, the comparison is a spinning disk or a SSD (explained above quite nicely). I prefer SSD for music, no possible noise at all. In theory SSD are more reliable, but you should have backups anyway.---

The manual suggests using either a 3,5" or 2,5" drive. Does size matter ? ( no pun intended) -----No. However 2.5 are even more expensive then 3.5, so unless there is a technical/space reason given by the manufactor (maybe you can fit two 2.5's and only one 3.5 for instance) than get the 3.5 SSD.----

Are there sonic differences in the different available brands? ----I've used many brands, I have not heard a difference, and there shouldn't be one with an SSD. I just go with the one that has the best warranty and specs for long life.----