For $600 it looks very good value (if you need a basic >5.8GHz analyser) as long as the RF performance meets your needs
I'm not really that experienced with the 492 but I did skim through the RF specs and a few things may be an issue. The std spec has no limiter protection for the first mixer up to 1.8GHz. So the damage level could be as low as +13dBm on low (typical!) attenuator settings.
Option 1 adds the limiter.
If you want to do any work on narrow spans then option 3 adds the phase lock option on narrow spans. This would be a very attractive option because it also includes a 100Hz RBW filter.
Unless you hit lucky and bag something like an HP8592 (or the vastly superior HP8561/3) for a stupidly low price then I think you will struggle to get better value for money than the $600 Tek492 even if it has no options fitted.
The other alternative is to get something like a Rigol 815 and build a simple external downconverter from 5.8GHz.