Like several other reviewers, I've become disappointed with Moleskine products because the weight of their paper is starting resemble the pages of my mum's 1950s school bible. I'm stuck with my 2018 page-a-day pocket diary for now, but having just filled a Rhodia A5 dot notebook (which I use for my bullet journals), I thought I'd try a Leuchtturm.This is a first impressions review, but I don't see why my opinion might change over time, so here we go.The notebook is well made with a sturdy cover that's got a *little* bit of flex; nowhere near enough to call it rigid, but certainly protective and of good quality. The product description from Leuchtturm states that there are 8 removable pages in the book -- you wouldn't know without studying them really hard because the perforations are very fine, but they're the last 8 sheets in the book and part of the set that are numbered. However, the very last one of those 8 (the last page in the book) is actually not detachable because it's glued at the spine to the inside back cover.There are two page markers, one patterned and one plain. Quite handy for a bullet journal to have more than one of these.I tested a range of pens on the (second to) last removable page of my notebook. (read: I sacrificed a page, for SCIENCE!)My go-to pen for my bullet journal is a Pigma Micron 05 and I was NOT disappointed at how this notebook stood up to it. There's virtually no show through at all when you turn the page, and holding the page outside of the book after it's detached, you can barely see the ink at all. I found this to also be the case under several other pen types, including roller gel pens, fountain pens, highlighters and markers.So, if you're fussy about show-through, gel pens and fine markers are both viable options -- unlike the pages of Moleskine books which, in my experience, show quite badly under gel pens. I also found that gel dried slightly faster that it does on Moleskine pages -- less ghosting on the opposite page when you close your notebook quickly after scribbling something down and far more lefty-friendly!The only thing I did notice in the minus column for gel pens was that the paper "gave" more under them. What I mean is that there was a mild indentation when I used a gel pen. The Pigma Micron was "silent" on the reverse of the page.The only two pens I experimented with that bled through the paper were a Sharpie marker and a Letraset Promarker, but those suckers bleed through (almost) EVERYTHING!The pages handle fountain pen ink admirably. I tried two kinds and neither showed through. The paper did buckle temporarily in one case (Diamine Shimmering), but it smoothed out again after the ink had properly dried. Of course the quality of your fountain pen's nib will be a factor, but my experience of writing with both a 1940s Parker 45 Flighter (fine nib) and a 2017 TWSBI 580AL (stub) was smooth and virtually drag-free.A 2B pencil showed up well on the page. A Rotring Isograph (0.4) dragged HORRIBLY, no matter how lightly I tried to use it.I've attached a couple of photos of the front and back of the sacrificed page of my notebook, so you can see for yourself the level of show through. Bonus photos of an attachment-free way of letting your notebook keep your pen handy.I don't know yet if I like it enough to switch permanently from Rhodia dot grid notebooks but, overall, I'm very pleased with this notebook.(Note to Amazon: why are some colours of this notebook more expensive than others? Are you punishing people for buying books that aren't muck-coloured?)