"So far I am struggling to see what has been improved."
But there were also positive comments.
Ian Lowes, managing director at Lowes Financial Planning in Newcastle, said: "We encountered some login issues this morning (9 May), which were quickly fixed but beyond that, everything thus far looks good and indeed, much better than expected given that we were prepared for some serious disruption.
"I am sure we will encounter some issues over the coming weeks while we get to grips with the new system and we know there are certain aspects of the service that will require work but initial signs are very good.
"The success of the switch over so far, is without a doubt, down to the significant amount of preparation time and effort invested by the Cofunds/Aegon teams."