Im kind of with SRCJJ on this one. I wouldn't go as far as saying he is finished but he has certainly degressed since joining.
I think its quite clear he is struggling to get down quicker and his reflexes have certainly slowed down. Bolasie scoring that goal at the Emirates at the beggining of last season signalled the decline for me. Most PL keepers would have saved that.
Woj has had nearly two years at Roma and has done a bit of growing out there. 2nd best clean sheets this season which aint too shabby. I'd like him back here next season, he still has a big future IMO.