I replaced the Omni with a Jack. It works much better. It gets great HD reception. Frankly the Omni would not pull a signal 3 miles from the stations.
I will say for distant VHF the Jack won't pull like Directional Batwing on a periscope. However, the Jack is a straight-in replacement. I am not sure how I would mount a periscope. I was in Buena Vista, Colorado, and my neighbors had the directionals, I couldn't get anything on the Jack even when I adjusted. I was told you could get a some VHF there. When I was in Denver it worked great.