Hi Nick --
My setup is pretty similar: an R7 mounted 5' above ground and an IC-706 running 100W. 40M is my favorite band. The ground conductivity is poor, but I'm on the top of a ridge that drops off steeply to the west, south and east, so that helps.
I installed my R7 a year ago and have worked 70-80 countries from the west coast on 40m. The Pacific, VK/ZL, JA are easy as is most of the near east. I also work EU long path in the winter mornings (they are beaming LP, whereas the R7 is "all path"). So it works pretty well for DX. I put up a 40M dipole at 35' a few months ago for comparison. The R7 and the low dipole are about the same for DX. A/B tests show little difference. Maybe the R7 is a bit better for the signals >5000 miles. However for daytime local work and for US contacts at night, the dipole is *much* better by 2-3 S units, sometimes more.
Thanks Kevin - I had my R7 up for about 6 months and never really used it that often, then when monsoon season started I decided to lower it down. I decided to put it back up on a tilt mount but tore up a tendon in my leg so the task to raise it back up again had to wait for 3 months of rest. I did just get it back up and have been testing it to see how well it works since I heard so many internet posts say it is a good antenna but I have never had an another vertical to compare it against, why the reason for this post.
During the day on 40m, range is between 400-800 mile
Sunset to early evening on 40m, I can hear the east coast 1500-2000 miles S7 to S9+ but they just faintly or barely hear me, and that was my concern, I thought it would be better. Also I hear Roberto in Italy loud and clear as usual and I am hearing Russia quite well too.
I am ordering a fiberglass mast so I can get a Doublet up in the air for 40 and 80m so I hope that helps with reaching the east coast with 100 watts. Will see what happens then!