I don`t understand how an Omni directional aerial can be a winner in any TV reception stakes.
I tested an omnidirectional aerial back to back against my preferred canal boat aerial (a DM Log Periodic) and it didn`t perform too well , which is what one would expect.
As in so many things in life there`s no such thing as a free lunch, and a directional aerial will pick up far better than an omni diractional aerial. Similarly it will reject unwanted signals far better as well.
The "free lunch" moral also extends to the size of aerial too. Basically, all other things being equal, the bigger the aerial the more gain it will have, i.e. the more signal it will pick up.
It is very important to realise that a low gain aerial cannot be made equivalent to a high gain aerial simply by using an amplifier, for simplicities sake, that`s an inferior type of gain !