I use Roccat as main, and Safari as secondary - would highly recommend Roccat, especially the latest 3.5 is quite the performer.
I like Safari too, although sometimes it can hang for no reason.
I have tried many other browsers (tried over 20 now!) they all have a certain subset of problems, I find Roccat and Safari to have the least amount of problems.
I hate with Chrome that when you have too many tabs open you can't actually see what they are, and further more it becomes hard to click them as they are so small and the close button takes up the whole space. Safari and Roccat puts them in an overflow menu which can be annoying (Roccat however has VisiTabs as well as the normal tabs which gives a preview of each tab, and you can just scroll through them, no overflow menu and the tabs always stay the same size no matter how many you have. This is a great option for me. I'm also not keen on Chromes "we must take as much data from you as possible implementation) I also kind it ugly (personal opinion, I know many people like it).
Firefox I find problematic is terms of when you have too many tabs it slows down the whole system until I close it, many websites also don't seem to function correctly for me, unlike the WebKit browsers which work fine.
I have also tried Omniweb which functions fine, (although it has crashed a few times for me) but my main problem with it is it looks so dated and the tabs have to be in a drawer, I like my browser to be maximised and you can't do that in Omniweb as you can't see your tabs… Plus I find Roccat faster and more stable so there really is no point in trying to like it!
Don't even get me started with Opera… I can't even get Facebook to work on it (I haven't tried Opera Next yet I must admit - that's only because their server was sooo slow I gave up trying to download it)
Edit:
I felt it was unfair not to try Opera Next and tried to redownload it (Opera's servers are still sloooow, so I gave up but luckily macupdate had it and it downloaded fast).
Basically it is shockingly bad, it's basically a reskinned Chrome rebranded as Opera, losing most of the functionality the original Opera had, but whats worse is it has no wear near as much functionality as Chrome either… So I will be deleting it.