Cyrano, BHX - MJV is 1633km/881nm, so with a range of 2500km the 400 would do this route with plenty to spare. However, although I personally would relish the opportunity to do such trips, the 400 has obviously a different cabin environment to the A320/737 types which usually operate such a route, so passenger opinion would be important, but as some have said on here, some pax really couldn't care less what they're flying on as long as they've paid next to nothing to do so.
It does please me to see comments, such as that from saman on here, and on other flybe threads, that the 400 is generally well-liked by passengers, and I must admit to being surprised at the dislike of the 146.