Wow - so much negativity and conjecture from people who are, if you don't mind my saying so, unlikely to have a clue what they are talking about.
Whereas you do, of course?
It's not easy or wise to just guess how structurally sound something is by just looking at it.
Unless you have some expertise in structures.
I confess, I have two bikes from Planet X that I've been extremely happy with, so I'm probably a little biased.
More than a little biased, judging from the extensive group d your post covers.
I think I'd trust Planet X to have got this right.
Planet X have got what right? They neither design nor build their frames. They're a bike assembler and retailer, nothing more (Not that there's anything wrong with that as a business model)
One of them is an old Pro Carbon, which to my eye is even more compact than the new version, and mine (I'm 6'4 on a bike with 56cm seat tube) probably has more seat tube showing than the one pictured above - it hasn't broken.
Just because something has never happened to you does not mean it has never happened to someone else. I've never broken my left leg, but it does not follow that left legs do not break. A correlation of 1 is the classic statisticians joke.
Actually, I think it's rare to hear of Pro Carbons breaking, and there seem to be plenty of them out there.
No one is singling out carbon in this thread. The matter under discussion is compact seat stays and the effect it may have on a bikes structure, and to a lesser extent the aesthetics. Me thinks you both protest too much considering no one is having a pop at your bikes frame material.
I think it's a fantastic looking bike and disappointingly for all the people that love to hate Planet X, it'll probably have the performance to match.
No one is singling out Planet X in this thread. The matter under discussion is compact seat stays and the effect they may have on a bikes structure, and to a lesser extent the aesthetics. It just so happened the photo used was of a Planet X mount, but could equally have been a Giant, Trek, Felt, Spesh or 101 bikes for dozens of brands.
In summary, we get it, you have a Planet X bike and you like the budget bikemeisters. Well, no one is really suggesting there's anythng wrong with Planet X per se, so I'm not sure why you're so touchy.