I'm/was longtime Opera 12.x user. Sadly that this browser is no more developed :(
Slowly is coming time for change. Thanks for several tips in posts above.

Been using Firefox for years and served me well. I might try out Pale Moon sometime just to have a backup web browser.

Firefox Nightly 64bit

I've been using 8 different browsers (for testing my sites) and my favourite is Chrome (definitely better than all the rest).
My second favourite is Opera, for being stable and quick. After Opera, I'd say Comodo Dragon, but that's just another chrome.

I don't have any issues with it on Linux (KDE). Just install a matching GTK theme (like gtk2-engines-oxygen for example).

What kind of stuff is in Chrome that we should be wary of? I've always felt like Google has some alterior motives with it under the hood, but am not really sure about concrete things that go on in there.

I have been using Firefox for some years now.

Tracking searches, website access, usage of Google online tools, owning whatever goes through their services, possibly correlating that with Google +, YouTube and Gmail accounts. Biggest spy in the world right now. Their browser has more of these things integrated by default, that's why I consider it more dangerous.

Chromium and DuckDuckGo should help get away from that a bit.

Ah yes, that's the sort of stuff that I've sort of assumed was going on but for the tracking site access that doesn't go through their search engine bit of it I have no concrete evidence. It's a tough thing to balance -- I love the convenience of having all my bookmarks and such carry over to every device I have, but I hate that Google is probably using that data to profile me.

I did change my default site address bar search engine to DuckDuckGo a few months back at least, and that plus no cookie cache via Incognito mode helps a bit... but yeah, subconciously whenever I use Chrome it always feels like someone is recording everything I do.

QupZilla is really nice:
http://www.qupzilla.com/

I still use Iceweasel (Firefox) as my main browser, because of the RequestPolicy add-on:
https://www.requestpolicy.com/
https://requestpolicycontinued.github.io/

Firefox is shitty, laggy and buggy too but all the other browsers annoy me too much so Firefox is my favorite.

I love Firefox 32, but I wish Mozilla could improve its memory usage.
Also, I'm puzzled about version 33 changes (yahoo,ads).

Huh yahoo, ads? Did I miss something? Of course I might not be seeing that because of addons I use.

Not in my experience. It's been pretty good with little to no lag and zero bugs. And i usually run with 200+ tabs in the browser.

I've had a crash now and then with Firefox, but that only happens once in a blue moon.

Privately:
Pale Moon
All the good from Firefox without the bad.

Professionally I need Internet Explorer, Firefox and Chrome.
Due to personal preferences I also use Pale Moon whenever possible.