Cannot...resist....reply.....
Lynata said:
“Astartes caliber 0.75 is much longer than Non-Astartes caliber 0.75 and thus does more damage.” (often accompanied by alleged visual comparisons such as between these and these kinds of ammunition) [...]
As for your reference visuals for calibre, it can be a combination of length or girth, as can be seen in a link like this: http://tinypic.com/view.php?pic=140g3o3&s=5 . The images you provide show different caliber ammunition, which can't apply to this argument as none of the material indicates caliber changes. The extra 2kg of the bolt pistol or the extra 11 kg of the bolt gun can't possible be all armor to resist "battle stress."
Lynata said:
"But shouldn’t Space Marines still be better and way more awesome than others?"
And they still are. I notice that a lot of people get caught up on very basic concepts such as the AP of their armour or how many dice their weapons do in damage.
Isn't that kind of what you're doing? Obsessing over why they are 'allowed' to do more damage than the sisters and DH characters, and that at high levels they (and tougher DH characters) become immune to low end weapons?
Lynata said:
“The Sisters of Battle are exceptionally well equipped, with armour and weapons the
equal
of any Space Marine Chapter."
- page 2 of their current Codex
It also says "yet must forego the more advanced lifesupport systems and strength enhancing abilities used by the Space Marines" on page 9, which is in direct conflict with that sentence. It also says "Even the Space Marines may be called upon to aid an Inquisitor should the threat be greater than he and any locally requisitioned forces are able to counter." which implies that the sisters may not be enough. My comment is a stretch, I know, I'm just pointng out the inconsistencies that GW has within the pages of a single book.
And the SM codexes also say "Armed with a fearsome bolter, protected by a suit of power armour and the product of intense training and genetic manipulation, he is far beyond a mortal man, transformed into a lethal superhuman killing machine" which implies he is no longer 'mortal.' It also says "A Space Marine is no mere man, he is a superhuman being..." which tends to imply that they're no longer 'mortal.'
Lynata said:
The two systems work okay as long as you don’t mix them.
You're right, DH and DW aren't totally mixable, and DH and RT aren't either. However, put two characters of the same or similar xp in the party (high RT or Ascension) and have a competent GM that allows each character their own screen time for their character's specialty and you will probably have a good time without adjusting the gear or stats significantly.