Buying a simple laptop or computer just means you are building your own streamer. Hence that is not a different option.
Well yes and no as I see it. Firstly I would not go so far as having a dedicated laptop for music streaming. I know there are good reasons for doing this, but I'm really not that fussy. I'm not chasing 'cutting edge' performance. I would use our usual 'general purpose' laptop, which is soon to be replaced with something more up-to-date. This approach appeals to me as I like the idea of pieces of kit performing multiple functions rather than having lots of bits and pieces to do different things.
Nevertheless, if I was convinced that a dedicated hi-fi streamer, as opposed to one self-built from a laptop, offered vastly improved usability and convenience then I might opt for that.
I suppose that whilst I'm basically very happy using a laptop I wonder 'am I missing something really obvious and important here?' I like the idea of keeping things as simple and streamlined as possible and I accept that often this is incompatible with achieving the best performance.
Pete