We went with MensUSA and are getting a poly-rayon/viscose blend. It's a little hard to navigate their website and find the vegan options, but I called 1-888-784-8872 and spoke to Liz (x224). She set us up with a great two-button tuxedo package, including a silk-free bowtie & cummerbund. Liz was not only helpful and confidence-inspiring, but also gave us a great discount, making MensUSA the best price I found. We're looking at buying for not much more than the guys would have paid to rent a tux. And they'll have a nice one that they can hang onto. (Discounts at other places for the bulk order were not quite as steep, keeping those sites at about $250 for the package.) Every store that I spoke with said that the poly-rayon blend is significantly nicer than the straight poly fabric, but you can also cut costs down by another $20-40 by going with straight poly.
Unfortunately MensUSA doesn't have a nonleather tux shoe option, so we will have to find those separately for the guys who don't already own tux shoes. Info coming soon - I have emails in to confirm the 100% leather-free nature of some shoes I found.
