MIB...what's cheaper to mail? box or tube

Help...... I need to buy supplies for our DIY message in a bottle STD's, ASAP but I'm not sure which would be cheaper in postage, the mailing tubes or the square boxes. Can you please share your costs?

I'm not for sure which is cheaper..b/c I only had the option to get the square boxes from the designer who did our invitations. We ended up paying about

$6- $7 per box (I think). It got kinda expensive. We had to mail out 30, but I wouldn't change my invites - I love the message in the bottle.

are you using glass or plastic bottles? we used plastic and didnt use a box or tube! we just waxed the tops. MUCH cheaper!

we used 6" glass bottles in the boxes and paid $2.71/invite. we didnt load it with sand either. i couldn't find a tube that was the perfect size without spending an enormous amt of #, and i ordered the bottles and boxes at the same time from the same company.

EDIT: not $2.71/invite - it was $2.71 to MAIL each invite

thanks a million everyone!!! i just got done with my excel spreadsheet and i have 116 rows!!!! yikes! i'm going to have to really sit down with FI tonight and decide who is actually getting the STD/invite and who is just going to get an announcement....

We mailed our glass MIB invites in boxes. They were filled with real sand, shells and a charm on the end and cost about $5.74 each EVERYONE made some sort of comment about how much they LOVED them, and how they were the best wedding invites they had ever received. With that being said, it was well worth the $$.

edited my original post - see above