I never had stock coils, but I replaced the ones the bike came with, with Dyna 5ohm coils + Hondaman Ignition and I saw an increase in spark strength. They fit great and look pretty factory IMO.
If I remember correctly, I believe Z1enterprises had the best price.
Some pics of the coils on the bike. With the gas tank on, you don't seem them at all unless you really get under it.

