Is there any performance issues in using Omega theme with Context, Delta and Panels modules?
it depends on your site and server configuration. if you get alot of anonymous traffic that doesnt require users to login, you should be fine as the cache would handle alot of that load. Also be sure to turn on js / css aggregation. I've built many sites with those modules combined and they run fine. But if your all about performance, you can just do everything by hand and write your own templates/css and not use the bloated ones they have, but you'll be spending alot of time. in that effect you'll have total control over what gets outputted to the user.