This review is coming from an individual who has been using the Norelco G370 before. I absolutely loved the G370. The versatility of that trimmer is nothing short of amazing. It had many attachments - adjustable lengths, nose trimmer, close shave trimmer, fine head, regular head, and I believe I'm missing one, but oh well. All you have to know that it was my favorite trimmer. The biggest downside was the charging time, and the discharge time. It needed 10 HOURS, to charge for 30 minutes of use. Needless to say, it wasn't always there for me.
Here comes the Norelco 5100. Right off the bat, what really caught my eye on this product was the 5 YEAR WARRANTY. Yes, you heard that right. It's completely optional, as you have to register for the 5 year warranty. I believe if you don't sign up for it, you get a standard of 2 years.
Anyways, back to the actual trimmer. It's much bigger than the G370. However, it has a nice heft, and shape to it. It comes with a regular buzzer, and 3 attachments. One being a very short beard setting, medium beard, and long beard, though there's very little difference between medium and long. It has a knob in the middle that rotates, and each rotation determines what offset the blade is from the attachment. It ranges from 0.4mm to 13mm, with 0.4-7mm going in 0.2 mm increments, then after that it's 1mm. It gives you a decent gap between lengths.
The unit itself is actually completely waterproof. You can wash this thing right after you use it to clean it all off. I don't actually turn it on while it's wet or under water, because i still don't want to risk it, but know that i've washed it every time i trimmed myself. This thing also works on hair, too. I've use the medium beard attachment and adjusted with the knob to the setting i like, and start cutting. It cuts really well, for both hair and beard.
The battery life on this thing is amazing. 1 hour of charge yields 70 minutes of usage. This is lightyears ahead compared to the G370's 10 hour charge for 30 minutes of use.
Overall, I would recommend this unit to anyone who is considering it. Hope this review was helpful.