I love read it later services and have used them for many years, but it seems to me as though Pocket is dominating the market, and undeservedly so.
If you want to store lots of different media Pocket wins, but Instapaper is by far the best when it comes to pure reading and enjoying a long web article how it was meant to be enjoyed.
When I say ‘how it was meant to be’ I mean with the correct images and alignment, but with the clarity that these services are supposed to bring.
No matter how often I try, Pocket continually fails to deliver many images at all and it also reverts to the standard Safari view very often. Instapaper, however, delivers 99% of the time, and it delivers a reading experience which is far superior, in my opinion, to any other read it later service.
The first is somehow still the best…