FLX Extreme Drysuit review

Casey McKinlay
Project Director
Woodville Karst Plain Project
Number of Dives: 12 Number of Hours: 50 Based on my experience over the past few months, “different” is the best way to characterize the new FLX EXTREME compared to the TLS350. Superior in some ways but less so in others. Less so primarily due to reduced flexibility but not to the point where it becomes uncomfortable or limiting. For example, when doing a multi-hour dive in cool or cold water, flexibility is already limited as a result of heavy undergarments, base layers, electric vests, etc. When wearing heavier undergarments where reduced flexibility is already a factor regardless of suit type the FLX EXTREME has advantages such as durability and warmth. The amount of flexibility lost is really not that relative in this scenario. When wearing light undergarments, diving in warm water or for shorter dives you may not realize the benefits of the FLX EXTREME and may prefer the flexibility and comfort of a TLS350 or FLX50/50. As for durability, I expect the FLX EXTREME to be more durable long term compared to the TLS350 with less chance of holes and leaks and probably a more durable suit for travel. I had DUI add the optional Cordura overlays for increased durability. I asked DUI for dry weight comparisons on some of their suits: Weight Comparison with Size 10 Turbo Soles
TLS350 7 lbs
FLX EXTREME 8.85 lbs
CLX450 9.85 lbs
FLX50/50 11.1 lbs
CF200 11.8 lbs
  The FLX EXTREME is 1.85lbs heavier compared to the TLS350. Another nice feature with the FLX EXTREME is a heavier base material to bind to for P-Valve or Heater Plug thru-suit connections. Be sure to request the internal reinforcement patch for these thru-suit connections along with specifying the location when ordering. My Halcyon exploration pockets also feel like they have a more firm foundation and the suit can handle the added stress where the pocket attaches to the suit versus the TLS350 material. The FLX EXTREME was also less prone to bunch up in key areas and did not squeeze like the TLS350 especially behind the knees. I can confirm the FLX EXTREME was warmer on several 10+ hour dives in 70 degree water compared to the TLS350. This was especially noticeable on the shallow portion of the long decompression using both DUI Thinsulate Ultra 400 and Xm450. I believe the additional weight and thickness of the fabric does a better job insulating the diver. Finally, I was surprised at how fast the outer material of the suit dried post dive. I was expecting it to take the same amount of time as a CF suit to dry but this was not the case. It dries quickly. Please be aware that I’ve been using DUI products for a long time and I was asked by DUI to evaluate the product so my observations are to some degree subjective when it comes to the brand. However, when it comes to the specifics of this suit I have tried to be as objective as possible. I like the suit and believe giving up some flexibility is a reasonable compromise for all the advantages I get in return. Going forward I will continue to dive a TLS350 for North Florida cave exploration dives since the variables are constant; temperature, bottom time, undergarments, etc. I am also fortunate in that I do not have to use my exploration TLS350 for other dives so it remains in excellent condition with very little wear and tear. At the same time, the FLX EXTREME will easily meet the requirements of a primary exploration suit or back-up suit but would also be a great everyday suit that can withstand the abuse of regular diving in addition to the demands of exploration diving. I believe the FLX EXTREME would be an equal if not better choice for an active diver diving in more types of diving environments. I believe the FLX EXTREME material will also be more durable and less prone to holes and leaks over time. And of course the most critical feature: the FLX EXTREME can be ordered ALL BLACK.