What do they mean for "long throw driver"??


I have a pair ot Totem´s Sttaf with a long throw bass/mid unit driven by a Primare I21 (2x75 W). Just how much can the staff´s move (excustion) safely?? I like the sound a lot, but I want to be sure if the staff´s can take all the watt´s the Primare can offer (without clipping the amp). The amp goes from 0-79 (volume) and at about 45-55 depending on the music program the mid/woofer is really moving and I want to be sure that I am on the safe side (not overpowering the speakers). My room is 10x16. Any comments out there??
tiofelon
Post removed 
As far as driving them goes, use your ears. If you hear the least bit of distorted sound, back the volume down some, until it sounds right. It could be either the amp or speaker distorting, but that(distortion) is a warning sign.
Thank you for your responses. As I said I like my current set up and I don not want to ruin the speakers! I just think that the mid/woofer (5 1/2") of the Totem´s look kind of fragile. Thnaks again.
Don't expect too much from a $20 woofer - definitely be careful not to over drive them.
Just one comment about magnetic gap. It is very narrow with typical (overhung) design where coil is much longer sticking outside (overhanging) of magnetic gap. Only part of the coil is at given moment in the main magnetic field. The other design - not very common underhung type has narrow coil and wide magnetic gap. This design is more linear (lower distortions with large displacements) but is more expensive because requires much larger magnet. Only few manufacturers use underhung speakers Acoustic Zen Adagio being example for the woofers or Morel Supreme for the tweeters.
Check some of the DIY speaker sites and you'll see the xmax (throw) is probably 6-7 mm (apprx. quarter inch) at most.Anything past that is pure distortion.Like Shardone said, you can't expect much out of a $20 driver.Now that doesn't accout for any tweeking the mfg. may have done.

You can figure about 10% to 15% of retail is the cost of all materials for the speakers.