Have not tried it yet for 7950s. I use GUIMiner-Scrypt on my 7770 (no overclocking or such).
Is there any kind of benchmark for GUIMiner-Scrypt for 7950s that I could see? I'd LOVE to use GUIMiner as opposed to CGMiner, but was unsure if I'd lose some performance.
Well, it's just a frontend to cgminer. The performance is the same; it even gives you the command it send to cgminer if you check the console.