Sounds like a very good move. Middlesbrough have been defensively sound for a number of years also so he shouldn't be too busy there. I've been just looking at their goalkeeping situation at the moment.
Valdes and Guzan have left the club.
Konstantopoulos is a 38 year old journey man with one cap for Greece. You'd imagine he wouldn't be much of a threat. He has recently signed a contract extension.
Then there's a former Real Madrid goalkeeper who, at 28, has only played twelve senior matches!
Randolph's biggest threat appears to be Connor Ripley, the son of former Blackburn Rovers title winner, Stuart. The 24 year old spent the last few years out on loan but seemed to excel for Oldham last season, keeping eighteen clean sheets and making the League One team of the season.
On a side note, if Patrick Bamford recaptures his previous Championship form when he won player of the season, it might be useful to have Randy and Cyrus knocking around at Boro. Christie, in particular, will be able to relate to Bamford's situation.