Aquilani is a good player who never fitted in. Babel was a talent who has a bad attitude and seems to just lurk about. Voronin, we made a profit on. Johnson is a good player. Itandje is just a joke. Josemi was *****, as was Kromkamp who was another we made a profit on, as we did with Mark Gonzalez. Pennant never played to his potential for us. Degen we got on a free and is a decent player who has injury problems, probably will make a profit if Stuttgart make his loan permenant. Dossena is another who never fitted in although he scored 2 goals against United and Madrid
Riera is undoubtedly another talented player who was largely inconsistant.
We never spent huge sums on any of them except for Aquilani who we will probably get a fair bit of money back from, we should break even on Babel and I reckon Glen Johnson is a decent right back.
The majority of the mistakes being under 5 Million, a fair few of them being free transfers.