texas--
If weight is not a concern, and it isn't to most of the guys on this site, the 30mm tube is better for several reasons. First, and most important, is the amount of available internal adjustment. The 30mm tube is larger and allows a larger internal adjustment range. However, as the power range goes up, the amount of internal adjustment diminishes. For example,the 8-32x Nightforce BR Model has 50 MOA of internal adjustment, whereas the 12-42x model only has 40 MOA. Second, and often debated, is the idea that the 30mm tube is capable of transmitting more light to the eye , especially in low light conditions. Third, the inherent strength of the larger tube is a considerarion. The 30mm tube is used on all of the high end scopes on the market. Look at NF, Leupold, Zeiss, S&B, Swarovski, US Optics, etc. USO even uses 34mm tubes on some of theirs. Hope this bit of info helps... CJ
[ 07-05-2002: Message edited by: Chris Jamison ]