The vast majority of financial services firms - 93% - do not believe that MiFID will be consistently implemented and enforced across the member states involved, according to research released by UK-based ea Consulting Group.
The research - which surveyed 85 representatives from some of the UK's largest investment and financial services providers - show a distinct lack of confidence that MiFID will be consistently applied across Europe, says ea Consulting.
MiFID comes into force on 1 November but there is still some concern about the readiness of both firms and regulators in the euro zone to comply with the new directive.
Earlier this week the Committee of European Securities Regulators (CESR) released details of enforcement measures for dealing with different levels of national preparedness for the switchover.
CESR said the measures would provide business continuity and "minimise the potential disruption to business that might be caused by late transposition of MiFID".
The ea Consulting research found that 40% of participants see "a lack of certainty" as the biggest threat MiFID poses to their business.
Around 29% cited distraction from 'business as usual' activities as the biggest threat, while only six per cent feel the cost of implementation presents the greatest threat.
When it comes to the cost implications of MiFID, 34% of respondents felt that compliance costs would increase the most, while 28% cited IT and systems costs and 13% believed that data capture and retention will see the biggest cost increase.
In terms of benefits that are likely to arise from MiFID, a quarter (25%) of the respondents believe that a Europe-wide compliance standard, creating a level playing field will be the main advantage of the rule changes, says ea Consulting. Around a fifth (20%) think that MiFID will make it easier to do business across borders, while 11% believe the new regime will make Europe a more attractive place for market entry.
Around 11% of respondents surveyed by ea Consulting believe that technology vendors stand to gain the most in a post-MiFID world, while a third think investment banks will benefit most.
A separate survey of of European institutional investors conducted by Connecticut-based consulting firm Greenwich Associates found the majority of firms feel the largest investment bnaks will gain the most from the implementation of MiFID.
Over half of respondents (55%) think the new rules favour major broker-dealers, while three-quarters of the institutions believe that MiFID will place mid-sized and regional brokers at a disadvantage.
"Our research suggests that the benefits of the new regulations will not be evenly distributed," says Greenwich Associates consultant Jay Bennett. "Europe's institutions expect that there will be winners, including the institutions themselves, large broker-dealers and electronic trading venues - which will benefit from the integration of markets and new requirements governing best execution and transparency. They also believe there will be losers, including smaller broker-dealers and exchanges."
Nonetheless, more than half the institutions participating in the Greenwich Associates study believe that MiFID will increase the transparency and depth of European equity markets, while slightly less than a quarter expect reductions.
Around 35% of the institutions expect MiFID to increase liquidity in European equity markets, while 20% expect it to reduce liquidity.