Hi everyone,
First time posting a thread here-- I've been getting so much great information from SB that I figured it was time to post something of my own here at long last!
I was just in the market for a new BC, having come off of an old (20+ years) Mares followed more recently by a Cressi Travelight (which I loved-- it was stolen, or so I thought, but that's another story for another time). Both fit well in size small.
For a variety of reasons I landed on the Hydros, but since I'm solidly on the border between two sizes according to their charts, I was looking for pointers on whether to go up or down-- I ended up with the small, and wanted to provide some of the thinking behind the decision.
For the sake of accuracy, I'll provide as much as I can about my measurements: I'm about 5'7.75", and range between 148-152 lbs. My jacket size is a solid 38S, and I border between size small and medium in t-shirts, etc. Waist size 30. Looking at the Hydros sizing chart, I'm either on the upper end of a small or lower end of a medium-- I understand that this is pretty specific, but others might might be able to graft this onto their specific situation if they're also borderline in Hydros sizing.
I went to my LDS, and tried both on, with a t-shirt and medium-thickness pullover, and it was really borderline there, too. The owner said he would solidly recommend me going with a small, though there was not a lot of tail to play with in any of the straps should I ever want to get into drysuit diving, for example (for now I'm a solid warm weather diver), and he said that medium was not out of the question.
To his credit, he said, "buy the small. Dive with it. If you really don't like it, come back and I'll exchange it for the medium."
So I bought the small, and once I got home I put on my thickest wetsuit (7mm) and tried the Hydros on on top of it. I took some pictures, which I'll post here; suffice it to say, considering underwater compression, coupled with the fact that, for now, 7mm is the bulkiest I'll be diving in, I think that small was the best choice, though I'm very interested to hear if anyone has been in a similar situation and either agrees or disagrees.
I will say that the waist belt does feel quite high, and there's not a lot of room to release in the shoulder straps to relieve this.
Also, a major disclaimer: I haven't yet dived with the BC, so please take this all with a large grain of salt. As soon as I do dive with it, I'll try and come back and post any impressions in case anything has changed.
Happy to try and answer any questions, if anyone is finding themselves in a similar place.
First time posting a thread here-- I've been getting so much great information from SB that I figured it was time to post something of my own here at long last!

I was just in the market for a new BC, having come off of an old (20+ years) Mares followed more recently by a Cressi Travelight (which I loved-- it was stolen, or so I thought, but that's another story for another time). Both fit well in size small.
For a variety of reasons I landed on the Hydros, but since I'm solidly on the border between two sizes according to their charts, I was looking for pointers on whether to go up or down-- I ended up with the small, and wanted to provide some of the thinking behind the decision.
For the sake of accuracy, I'll provide as much as I can about my measurements: I'm about 5'7.75", and range between 148-152 lbs. My jacket size is a solid 38S, and I border between size small and medium in t-shirts, etc. Waist size 30. Looking at the Hydros sizing chart, I'm either on the upper end of a small or lower end of a medium-- I understand that this is pretty specific, but others might might be able to graft this onto their specific situation if they're also borderline in Hydros sizing.
I went to my LDS, and tried both on, with a t-shirt and medium-thickness pullover, and it was really borderline there, too. The owner said he would solidly recommend me going with a small, though there was not a lot of tail to play with in any of the straps should I ever want to get into drysuit diving, for example (for now I'm a solid warm weather diver), and he said that medium was not out of the question.
To his credit, he said, "buy the small. Dive with it. If you really don't like it, come back and I'll exchange it for the medium."
So I bought the small, and once I got home I put on my thickest wetsuit (7mm) and tried the Hydros on on top of it. I took some pictures, which I'll post here; suffice it to say, considering underwater compression, coupled with the fact that, for now, 7mm is the bulkiest I'll be diving in, I think that small was the best choice, though I'm very interested to hear if anyone has been in a similar situation and either agrees or disagrees.
I will say that the waist belt does feel quite high, and there's not a lot of room to release in the shoulder straps to relieve this.
Also, a major disclaimer: I haven't yet dived with the BC, so please take this all with a large grain of salt. As soon as I do dive with it, I'll try and come back and post any impressions in case anything has changed.
Happy to try and answer any questions, if anyone is finding themselves in a similar place.