High performance coils cause no harm, but are of no benefit either. This isn't a 1960's points/condenser system with spark plug wires. There is very little (negligible) voltage loss with COP ignitions. You won't gain anything at all from using higher claimed higher voltage coils.
COPs quality depend more on reliability of construction. The Gama coils from Global have a good reputation and a decent price. Accel and Granatelli both have high rates of failure.