Nothing's as fast as Radmin, don't get me wrong... I have a zillion wishes for it and Linux clients etc...but the CORE is quite impressive. I have USED evertyhing- PC Any, laplink, VNC, Dame, MS terminal/ RDesktop. Only three flaws- doesn't work well with XP remote desktop having been used, doesn't do anything with more than two medium-res displays (I think it craps out at a measly 2048 pixels wide), and doesn't have any clients for Linux or mobile devices. Other defects have been addressed by good support systems, like somtimes glitchy NT4 installs and BSODs.
There are workarounds for everyhting- use non-matrox vid cards or cards that work in "windows" dual-display mode, reboot with remote desktop boxes so that Radmin can take control again, and use tightVNC otherwsie.
TIGHTVNC will help you on the linux side until Radmin gets organized. Even with the compression tweaks they've done in tightvnc, still not as fast as Radmin.. but since you can have java client and any OS full client, including mobile/linux/even zaurus Linux PDA its a good free backup to Radmin. Dameware also works well seomtimes, and you can push installation which is nice.
Radmin has almost NEVER failed on me. I will ALWAYS argue that the LOW cost of liscneces is well worth it, and liek everyone eagerly await the next version or a competitor who beats them to it, whichever comes first.
It has been few years since you have said this and I can't help but to agree more until today. Radmin has been very helpful to me working on different projects currently at hand. Thanks to all of that.