You might begin thinking about this by reviewing the comparison chart linked below. Note that most features of ESPlanner are now included in MaxiFi Planner.
Please also read this notice about plans for ESPlanner.
The case for switching to MaxiFi
One obvious difference in the programs is the platform and user interface. If having your plan in the secure cloud, accessible from any computer is a big plus then +1 for MaxiFi. Another big plus is that we do the updates to the program for you--no more downloading and installing the update for features or bug fixes.
We expect many or most users to prefer the web-based interface we have designed. Though it is different from ESPlanner and may take a short time to get used to, we think it's handier and easier to use and it certainly is much more pleasant to look at.
MaxiFi has some built in optimization features. You can run a Maximized Plan that will evaluate all the different Social Security benefit collection strategies and show you the one with the highest present value (this is very similar to what our Maximize My Social Security does for you, but it does its work in the context of your full financial plan). It also looks at different start dates for beginning your retirement withdrawals, annuitizing your retirement assets, and beginning withdrawals from Roth accounts first or last. It also allows you to look at any optimization that might result from changing your qualified retirement account contributions. These are all things you can experiment with manually in ESPlanner, but in MaxiFi Planner there's a one-button push to run your plan against these optimization features. MaxiFi also has a redesigned and robust Monte Carlo that has been improved over the Monte Carlo risk analysis in ESPlanner.
If these differences seem like an advantage to you, then you will probably want to move over to MaxiFi Planner.
The case against switching to MaxiFi
If you need the features in ESPlanner that are not yet supported in MaxiFi Planner and the case made above does not outweigh the benefits of the feature set in ESPlanner, you may want to stick with ESPlanner. You might also feel that ESPlanner is working fine for you now and wish to think about this later.