The only problem is the units sensitivity, which is pretty low at 88db. The woofer line array sensitivy may be higher, depending on how they are wire, and how many drivers are used. Woofer arrays tend to be in the mid 90db range, and if you use a 88db ribbon tweeter you will have to pad down the woofer array to match the tweeters output.
This power will be wasted in a passive crossover.If you have enough amplifier watts to drive the system it may not be an issue, but if you use single ended amps, you may not have enough power to drive them to decent sound pressure levels
Newforn research also makes large ribbon drivers.
www.newformresearch.com