"You are suggested to use the left extruder to print with PLA, while the right extruder to print with ABS"

This is a direct quote from the FlashForge Creator Pro 2016 manual, and the only qualm that I have with this printer. After some tests, I confirmed that this printer has the potential to use the right extruder to print in PLA and make excellent dualstrusion prints. The only thing you need is an improved fan duct.

As you can see in the attached photos, this fan duct allows for a visible improvement in print quality and accuracy.

You can replace the stock fan duct with this model easily, without the need to relocate the fan or make any drastic changes to your machine.

Instructions:

• Download and print the STL file in ABS using the recommended print settings.
• Make sure that your printer has cooled down before attempting to install this piece
• Remove the three bolts that secure the fan to the extruders
• Separate the fan from the included duct
• Move the fan away from the extruders and check if the new duct fits. Don't force it too much. If you have trouble inserting the new duct, carefully sand it a little.
• When you are sure that both parts fit without applying too much force, align the fan in its place (but don't put the bolts yet!)
• Install the new fan duct from below, so that it doesn't collide with the bands
• Re-install the three bolts to secure the fan to the extruders

Notes:
While it's possible to print this piece without supports, I strongly recommend using them. If you have Simplify3D, use the Customize Support Structures menu to place supports as shown in the included screenshots.