I used samp from 7-9, and have demoed each since v10, and for me, it seems to have gotten progressively flakier, and I could never get it to be as cpu-efficient as cubase, reaper or s1v2, despite the various buffering schemes. Your mileage may vary, of course, and at this point, with CPUs being what they are, it may not even be an issue.
While I personally didn't care for the floating mixer, it is pretty nice in most other regards, and the stock plugs are exceptional. Surround support is likewise very good.
Object-oriented editing was a selling point a while back, but you can insert fx onto clips in several daws at this point. Cubase and DP have also had the automation-style "clip gain" of PT since mid-last decade (drawing automation-style curves...not to mention inline pitch correction for quite some time now). Gaining the entire clip...pretty much every daw can do these days.
If you're a hardcore midiot, you'll likely be disappointed versus cubase (but to be fair, Samp is like PT in that regard, an audio editor with midi added later, versus a mature midi sequencer like cubase, logic or dp, with audio added later). If your needs are more basic, it's pretty decent. If you rely on the arranger or chord track in Cubase, you're out of luck though.
Having to use extra video editing software (and import/export cycle) to deal with standard video work was a dealkiller for me at my dayjob many moons ago (this is how i got sold on DP). Hopefully that's changed since then.
4 point (source/destination) editing was the exclusive domain of sequoia. If that has changed, yay! Afaik, it has not.
I guess overall that sounded pretty negative, but i wasn't trying to make it come off that way. It's gonna depend on what you need day to day. Honestly, try the demo. It could totally rock your world. Copy protection is challenge/response, so no dongle...whaddya have to lose?
BTW, when MAGIX bought yellow tools, they hooked me UP with independence libs...i'd had partial libraries previously, but Magix reorganized them, and i got one helluva upgrade...for nothing. Also, i must add that their support has always been courteous, prompt, and helpful. I won't ever bitch about the company or their treatment of customers in that regard