[CookieCrumbler]

Firstly, if the hardware of the dedicated server your server is hosted on is pretty good, which is most GSP's out there you should have no problem with hosting a 1000FPS server.

There is not much point in going over 1000FPS its just a waste and theres no real benifit to doing so.

Just use the following rate settings without pingboost.
// Set Rates
rate 100000
sv_maxrate 100000
sv_minrate 2500
sv_maxupdaterate 102
sv_minupdaterate 66
sv_maxcmdrate 105
sv_mincmdrate 66

And tell your players to
1. Goto there video card setting control panel and change Vertical Sync to "Always Off" or "Force off"
2. Set there rates in there client console to:

rate 100000
cl_updaterate 102
cl_cmdrate 105
fps_max 99
gl_vsync 0
ex_interp 0.01

If they have a very good video card

cl_updaterate 102
cl_cmdrate 105
fps_max 1000
fps_override 1
developer 1
gl_vsync 0
ex_interp 0.01