USER INTERFACE: Plain, simple, and straightforward. Very easy on the eyes. I think it perfectly represents both the simplicity of the instrument and the sound it was meant to make. The blue water-like strip on the top of the plugin's GUI seems to go hand-in-hand with the crystal type sound it makes.
SOUND: As far as sound quality goes, this plugin scores high. It manages to faithfully reproduce it's sound over a very broad key range, from about C0 to C7 if your counting octaves. The type of E-piano sound it creates is where one might not be intersted. The 4front EP module is basically a DX E-Piano. It has a very 80's digital sound character to it. However, if you are looking for a great FM-type E-Piano sound, then look no further...The 4front EP Module will suit your needs better than most commercial instruments.
CUSTOMER SUPPORT: 4Front is extremely responsive and helpful when it comes to customer support. George Yhoung (The man in charge) has always been more than willing to answer any questions and concerns that I have had for this plugin.
VALUE FOR MONEY: In my honest opinion, this plugin scores high in this category as well. While it does produce a very cliche type of sound, it produces that sound with very high sonic quality. Considering it will cost you nothing but a few seconds of your time to download and install it, you can't go wrong.
STABILITY: This plugin is beyond stable. I use it often for drafting piano lines and phrases as it loads quickly, consumes almost no CPU power, and never causes any crashes or system problems.
Overall, I think that if you are looking for an FM/DX type piano sound for one reason or another, you will be more than pleased with the 4front E-Piano Module. It's quick, easy, and above all...dependable. I personally never see myself deleting it from my harddrive.