I'd highly recommend picking up this bad boy while you still can given how well the game has been selling and I usually NEVER buy guides. This just one of those games that's actually worth having the geeky info.
Even if they patch the game to rework balance like they did in Dark Souls 1 it is still insanely useful to look at strategy tips on bosses before you've beaten the game a billion times. The wiki won't be fully updated for many of the item stats/descriptions early on.
Also i would like to point out the resale value of the Dark Souls 1 Guide on amazon
I believe I also got this one for $20 or $25 and the price went UP. I'd attribute it to the games being classics and the guides being pretty classy. Future Press did a solid job with the last one. Lot of interesting things to look at even if you've beaten the game. For every single enemy and boss it gives a lengthy strategy about what to do and avoid doing or how to attack it. Then they also break down every single attack the enemy does, how much damage each attack does, the type of damage, whether the attack tracks, the speed of the attack, the HP of the enemy, the souls you get off each enemy.
Plus there are very nice spreadsheets for every single item. They show the damage reductions for every upgrade level per each item. There are nice compiled lists for each boss soul to help you decide what you want to use it for. Locations of all the crystal lizards. Information on NPCs and what they can give you or drop if you kill them. They really do an excellent job of filling it with useful information so it's a book you go back to many times.
Really nice hard cover guides. Great for reading on the toilet.
I'd consider this a deal that many will overlook. Much better than spending $100 or whatever dollars on the statue.