Is anyone using the INRAD 2.8k filters in the Mark V.? If so, is it worth the money for this upgrade as compared to the stock 2.4k filters? It is hard for me to believe that .4k would make that much difference. -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.0.371 / Virus Database: 267.14.13/221 - Release Date: 1/4/2006