I've just remembered that, while you have to buy the Radio Listener's Guide for the latest radio reviews, they've recently their put older reviews online for free. Since the Roberts Stream 83i featured in the 2010 edition, and the Pure One Flow was in the 2012 edition, that means that you can read the full reviews here
http://www.radioguide.co.uk/Radio-Reviews/WiFi-and-Network-Radio/roberts-stream-83i-review.html
and here
http://www.radioguide.co.uk/Radio-Reviews/WiFi-and-Network-Radio/pure-one-flow-review.html
For all other WiFi radios (reviewed prior to the current year) start here:
http://www.radioguide.co.uk/Radio/products/wifi-network-radio_c26/
(That's the first of 4 pages of results).
Interestingly, the 2013 RLG quote I referred to above, starting with "Our budget WiFi radio recommendation is Pure's One Flow, £100, which offers a lot of functionality for the price" continues "Also well worth considering is the Pure Evoke Flow, £135. It has a crisp OLED display and touch-sensitive controls. . . . [i]The Roberts Stream 83i, £130, is the final radio we recommend in this category[i]".
So it seems that you're already looking at two out of the best three anyway!