To be fair they would make any property look worse unless you can hide them away from the normal approach to the house. Depends on the benefits, if good I could put up with the looks.
I'd only consider PV Cells if I had my entire roof re-tiled. That way you could use Solar Shingles which don't ruin the curb appeal quite so much. These are being used on a lot of new housing estates and don't really stand out.
