I'm surprised that you can get WRGB with a flat panel antenna like the Leaf or the RCA (you didn't give the RCA model but their ad shows all their amplified antennas are panels). Most small antennas don't do well on the low VHF channels 2-6 and often have trouble with high VHF channels 7-13 (WXXA is on 7). If the Terk is the HDTV1 it has rabbit ears which should get 6 when fully extended horizontally, although that might not be the best adjustment for 7.
Just to be sure, you really are getting WRGB as 6-1 and not as 45-3? The latter is a subchannel with WCWN, 45-1, RF 43. You said you get WTEN (26) well. How is your reception of the other stations from the hill: WNYT (12), WNYA (13) and WMHT (34)? You probably don't get 3ABN on 44 (W44CT-D); they're very low power. I can't get a good lock on them at 10 miles. I suspect they exist just to invoke Must Carry on cable. But I digress.
For the record, I'm currently getting WXXA the strongest of any of the hill stations. But that's using a homemade antenna optimized for channel 6.