I've had the Clarity Aloft TSO version and I'm fairly happy with it. Using it from the left seat on the A320.
Passive noise reduction works wonders. The main reason I decided to buy the headset is for reducing noise fatigue and from this perspective I can say it does an great job. Started with the foam tips and I was impressed at how much noise they blocked out. Better than any active noise canceling headset I've ever tested. Actually it so quiet it took me some time to get used to not having much sound feedback from the engines during takeoff and when I have the auto thrust off. The A320 is not an especially loud cockpit so when you have the foam tips in during the cruise it's eerily quiet. I leave it on the whole flight and am convince I'm less tired at the end of the day from the reduction in noise.
I find the foam tips put a slight pressure on my ear, and the foam next to the skin gives me a slight irritation during a long flight. After using the foam tips for a while I decided to order up some custom ear pieces. Went to an audiologist and they took the mold and the custom ear pieces arrive a couple weeks later. What a disappointment… I read that custom ear pieces were suppose to be comfortable but this was just not the case for me. Maybe I have sensitive ears, I'm not sure, but when I used them they were much more irritating than the foam tips and put much more pressure on my ears. After a long day I would even get a slight headache from this. Also, they did not reduce the noise as well as the foam tips! Unlike the foam tips that expand in your ear, the custom pieces just slot in thus there is a slight gap between your ear canal wall and the earpiece. Expensive, uncomfortable, and block out less noise…. On a Plantronic MS50 or Telex 5x5 I can see the use of a custom ear piece because it stays firmly in your ear to support the mic boom, but on the Clarity Aloft headset there is little point in going custom unless you find them particularly comfortable. Also, since the other pilots usually don't have a headset on during the cruise, every time we chat I have to take the right earpiece out so I can hear them. This is not a problem with the other tips as they slip in/out of your ear with ease, but with a custom piece it takes a little more effort to get them in/out of your ear so it becomes an annoyance every time you have to yank it out to chat.
Finally I tried the ear tips from my Etymotic HF5 earphones. So far this is the best option. These are triple flange ear bud tips (I cut off the smallest flange to make it a double flange- fits in my ears better). Since they are rubber you don't need to replace them like the foam tips. Not as good as the foam tips regarding noise reduction, but the comfort factor makes them far superior. I can wear them for 10 hour day no problem. Can buy them on ebay- search "triple flange ear tips"
Regular, Bluelink or Pro (TSO)? I don't fly in the U.S., and I've never had my headset looked at by an inspector so being TSO certified means little to me. The regular/Link Headset has a thicker cable and overall construction seems stronger than the Pro model which is kinda strange. I started with the Link headset but didn't want the bluetooth in the end so I exchanged it for the pro. The bluetooth device is bulky and adds weight with its batteries. I don't find the pro quite as comfortable as the regular/link design. I recommend the standard version without the bluetooth device.
I initially bought the Link Headset because I liked the idea of being able to listen to music softly during the cruise. When someone transmits over the VHF the bluetooth quickly fades out whatever you're listening to so you can hear the transmission. Sounds great in theory but in practice it becomes annoying because the music is turning off every transmission, then it takes 2 seconds to fade back on after the transmission. Also the bluetooth drains the battery on the iPhone. I prefer to just have the music continue playing on a lower volume rather than fading out during transmissions. The volume connector (that little box on the end of the cable) on the headset has a 3.5mm jack so you can connect your mp3/ipad/computer to it with a cable and the audio from your device will be heard along with the radio. This is a great feature! I connect my iPhone to it and play music through the headset. You could always buy a 3.5mm bluetooth adapter off of ebay to fit into it if you still really want the bluetooth function- cheaper and it doesn't fade out.
Mike boom is on the left side and the cable attaches to left side. This makes it ideal for the left seat, but a bit awkward from the right seat, but still doable.
Problem I initially had was the volume from my mic was too low. It's very annoying to talk on the radio or intercom without being able to hear your own voice. If I turn up the intercom volume loud enough to hear my own voice than the other pilots voice would be far too loud. Clearly it was a mic problem because the other pilot also complained my voice was coming through too soft. I had to keep the mic so close to my mouth I was almost chewing on it. What I eventually did was take the mic foam cover off and that solved the problem (It's a very thick foam cover and I guess it was blocking out too much of my voice projection).
The headset is feather light and just rest lightly over your ears. Took me a couple weeks to get used to the wires around my ears, but now I forget it's even there. Only complaint is when I put recline the seat and rest my head back the wire around the back pushes into my head. I have to pull it down so it doesn't do this.
Overall great headset and I recommend it.
See image of the etymotic ear tips I use:
