Supplier only has 705 in stock.

i'm getting ready to build some broadband panels and my local supplier only has the denser 705 material in stock. i don't think i have time to wait (i've set aside specific dates for downtime) to order 703. is this a big deal? can anyone tell me how different it'll be? thanks in advance, drew

705 will be OK except for reflection points where you have very shallow angles of incidence. In those cases, the high frequencies can tend to skip off. If you can only get 705 in the timeframe you need it, then I'd recommend putting some cotton or poly batting on the front of the 705 to help bring the HF absorbtion back up in applicaitons where the reduced HF efficiency might be an issue.