Do stands / spikes improve B&W 802N performance?

I have B&W Nautilus 802 Speakers. They are on the factory coasters. Do any stands / spikes exist? Do they improve performance? If so, who makes them and how can I purchase?

Krell FPB 200c Amp
Wadia 850 Digital
Cardas Golden Cross Interconnects / Speaker Cable
B&W Nautilus 802 Speakers
Get those puppies off the floor. The sound anchor stands are what I use for my 801s. The soundstage is much broader and bigger. The stand will elevate the speaker and prevent the speaker box from interacting with the floor.

After you order the sound anchors first thing Monday morning, get another single run of speaker cable so that you will now have a shotgun biwire configuration of speaker cable. You will notice more clarity,control, and ease in your system.

After that, if you still enjoy the sound of your system, perhaps getting a larger stereo amp or better yet adding another 200c will be another huge improvement. Good luck. I hope this helps.
Save your money and get the spike kit from your B&W dealer (generally supplied free by request). The problem with too much elevation and tilt-back for the N802 and N801 is that if your ears are lower than the midrange axis, the speaker sounds discontinuous because a severe 3 kHz suckout develops. Look from the rear of the speaker to the listening position and see if the midrange fires above your ears. If you have a low seat (34" ear height for mine), you may have to elevate the REAR of the speaker to tilt the midrange axis DOWN to your ear height.
Both suggestions above may be correct, but that is impossible to know without telling us anything about your room , its layout, furnishings, etc. I use them (N802's)in my theater, and the spikes are perfect in that application. However, the sound anchor stands may be the fix for what ails them. Whatever you do, for God's sake, remove those stinkin' casters. They are there to help move the speaker easily, and that's it.