Does the compressor head really need to be 100' from the panel? The head and tank can be separated on compressors fairly easily. The tank can be anywhere there's an air line, and keep the head/motor near the power supply - and run an air line to the system. IMHO the time it takes to separate the tank and motor/head, then add more air lines is far more efficient/cheaper than running all that heavy gauge copper.
That being said, I started my with a Harbor Freight 60gal (cough), but only because I happen to come across a sidewalk sale and the 1.5hp/60gagal was $200, factory reman, no warranty. That thing ran all day, 5 days a week for 7yr with zero problems (yes, ran ALL day to keep up with the media blaster, die grinder and machining/air tools). Finally the motor blew out due to one of the transformers blowing outside the shop. We never turned it off at night since the lines were so tight, would stay full all weekend if off. Well, when the transformer blew, the compressor just happened to need to fire up and was trying to on 110v single leg (neighbor wood shop called me Monday morning, frantic my shop was on fire). It fried so bad by the time the breaker popped, the shop was full of smoke and lacquer was dripping out the the motor vents. Stuck a 3hp 1ph 220v motor on until the head blew a valve and purchased a used reman Quincy 325 head. The 3hp ran that head for a few more years until the bearings wore slap out, so snagged a 7hp 3ph motor to replace it. Now the problem is the head runs at 400rpm with the biggest pulley I had (needed air, quick fix, so the pressure switch is set to 190psi and can maintain 90psi in the most demanding shop usage (80-90cfm @90psi for the vapor hone alone).
With that being said, I can't even imagine the starting draw of a 10hp 240v 1ph motor 100' from service.