Maybe the cost of switching will put you in the red for awhile. Most Software conversions do. However, the question to answer is when will it start saving me money and is it worth it? If you end up saving $1 per month over your old system, chances are you should stay put. If you save say $300 a month over your old software, chances are you should switch. Remember the law of sunk costs: whatever you spent on your old system is irrelevant, the best choice going forward should be the software that saves you the most. The money is spent on your old system whether you go with the new one or not.
2. Is it flexible?
Technology changes rapidly. Is your system properly designed to adapt for changes in technology? Does it have the technology-agility of a speed boat? Or is it a lumbering battleship, unable or unwilling to make changes?
3. What about the staff/company?
The staff that helps you with a new software can often determine the overall decision. A poor staff, rude one, or unhelpful one can be the difference between a good choice and bad one regardless of the software itself. Don't get caught paying for support. Support should always be free.