I am not an expert but I have been diving side mount for about 3 years now, after 23 years of back mount diving with about 20 years in back mount doubles.
Comfort depends on the rig - a larger rig like a nomad with doubles, stage, deco bottle, etc is still a lot of stuff, but it's easier than back mount, think that's even more the case with multiple stages.
A smaller rig like a Razor or SMS 50 is very comfortable and with smaller lighter tanks like AL 80s, AL 72s or steel 72s it's a joy to dive - almost like having nothing on at all. I think the learning curve is also a bit less steep with those particular choices and tanks.
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I think most of the concern over new divers learning in side mount is the potential for those new divers to confuse diving a side mount configuration with side mount cave diving - and then running off and trying out the new gear and limited skills in a side mount passage somewhere, with fatal results. I think that concern is valid as some people seem prone to doing incredibly stupid stuff, and even cave training does not do much to inoculate the truly stupid.
I was full cave before switching to side mount, but even 3 years and 170 or so dives in caves using a side mount configuration and maybe half that number of dives in side mount passages, I am still taking small steps into progressively tighter and more challenging cave to ensure I don't over reach or over step my ability.
Comfort depends on the rig - a larger rig like a nomad with doubles, stage, deco bottle, etc is still a lot of stuff, but it's easier than back mount, think that's even more the case with multiple stages.
A smaller rig like a Razor or SMS 50 is very comfortable and with smaller lighter tanks like AL 80s, AL 72s or steel 72s it's a joy to dive - almost like having nothing on at all. I think the learning curve is also a bit less steep with those particular choices and tanks.
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I think most of the concern over new divers learning in side mount is the potential for those new divers to confuse diving a side mount configuration with side mount cave diving - and then running off and trying out the new gear and limited skills in a side mount passage somewhere, with fatal results. I think that concern is valid as some people seem prone to doing incredibly stupid stuff, and even cave training does not do much to inoculate the truly stupid.
I was full cave before switching to side mount, but even 3 years and 170 or so dives in caves using a side mount configuration and maybe half that number of dives in side mount passages, I am still taking small steps into progressively tighter and more challenging cave to ensure I don't over reach or over step my ability.