Do you want the best headset? 
As you consider wireless headsets for your office, you'll want to know the differences between a DECT and Bluetooth wireless headset. We highly recommend staying away from Bluetooth headsets in your office for these reasons:
DECT 6.0 vs. Bluetooth: Interference and security
Being that so many devices operate on Bluetooth, the last thing you want to do is use a Bluetooth headset and get interference.
DECT headsets operate on 64 bit encryption and Bluetooth headsets operate on 128 bit encryption, so both will be secure. Once the headset is turned on and linked, the chances of someone listening in on your calls is almost non existent.
In addition, being that DECT headsets operate on their own frequency, you can get many more headsets in the same area without the concern of interference.
DECT 6.0 vs. Bluetooth: Wireless range
Depending on which class of Bluetooth device you have, the wireless range on a Bluetooth headset will be significantly less than a DECT wireless headset. Bluetooth classes:- Class 1 Bluetooth has about 330 feet
- Class 2 Bluetooth is about 33 feet (most common)
- Class 3 is only 3 feet :( (might as well use a wired headset)
DECT wireless headsets, depending on the model offer you a range up to 590 feet.
Keep in mind, to many of the same headsets in one area can still cause interference, so if you're planning on using a lot of wireless headsets, it's important to consider the proper layout.
Offices usually won't see any type of interference until 100+ DECT headsets are in the same area.
DECT 6.0 vs. Bluetooth: Compatibility
Bluetooth headsets in most cases aren't compatible with desk phones. There's some desk phones that have Bluetooth built in where a Bluetooth headset could be used, but is a solution highly not recommended.
Even if there's a significant cost savings, it's not worth the experience and headache it will cause you. DECT headsets are optimized for desk phones and depending on the model can offer you connectivity to a desk phone, mobile phone or computer.
DECT 6.0 vs. Bluetooth: Battery
MOST Bluetooth headsets you'd use for business don't have a replaceable battery, where as almost all DECT 6.0 headsets will have a replaceable battery.
Having to replace your headset out every 1-2 years because of batteries can be costly, especially in a large deployment of headsets. Replacing a battery, rather than a headset makes much more sense to me.
Conclusion:
All things being considered Bluetooth headsets are great for Unified Communications applications, but is not a recommended solution for desk phone applications. In addition, if you do have a UC application being widely used in the office and decide to use Bluetooth headsets, there's a high chance there could be interference issues.
That being said, if your office is highly spaced out or your an at home worker, a Bluetooth headset for your softphone or mobile phone calls would be a great choice!
DECT wireless headsets will give you superior sound quality, range, security and is built specifically for office environments.
