Yes, the i5-2500k is better than the 920. The 920 is a 3 year old CPU that probably is only available used on ebay. I have seen benchmarks of that i5 up against whatever low end i7 is available (950?) and it did very well, even exceeding performance with some applications.

I was simply comparing my 920, which again, is 3 years old. If I were building a mid-range "gaming rig" for a client, the i5-2500k would be ideal. If I were building something for myself, it'd definitely get an i7. We're talking a $120 difference between the two, which isn't a big deal if Uncle Sam is buying.