I've been using it and it seems fine.
The only thing I can say for the
DMG system is that there are times when you can hang some concrete narrative on the three failures. Basically though with Obsidian you have 3 rounds of the challenge to do things with.
Even after the big patch there are still math issues with the
DMG system too. So why not use something that has simpler and more reliable math?
Overall I've developed my encounter building to the point where I can confidently build encounters of either combat or skill challenge type and have them work equally well. In a way skill challenges are really nice to use a lot because failing them generally isn't lethal. Failing significant combat encounters usually initiates a
TPK. At best it usually means an awkward extended rest or DM cheese (exodus knife!).
Now, skill challenges CAN kill characters and can certainly beat up the party or even thwart them entirely. I would do it rarely, but if you don't make SC as first class encounters then you will end up with a lot of heavily combat oped characters running around. Even the more RP oriented players will go with combat options if those are the only ones that REALLY matter in the long run.
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