Digimatch antennas come in a few versions. Is this the one you have? The "outdoor flat panel antenna" - is it this one?

The antenna on the top is the old Winegard as in my link then the Digimatch antenna performs better is some areas. This particularly so when the local transmitters transmit vertical polarised signals (where you see the antenna elements installed vertically.) Having a portable antenna can also get you a signal in difficult areas if you try different locations and manage to get signal in one of those locations (a bit of a trial but can get the other party off your back.)

If the antenna on top is this one then it should have similar characteristics as the Digimatch. If you have the space to carry the portable antenna then do so. At each site wind up the antenna on top and see what sort of picture you get. If you don't get much then try the portable antenna. If after you do not get much value from the portable antenna then leave it at home.