I don't have much experience with sand in the R44, but a lot of dry dusty environments.
With over 500 hours on the helicopter, the effect has been negligible so far as I can tell. The dust does get everywhere, but I wash the helicopter very frequently. The blades get very dirty very quick and it hurts performance. Paint is wearing off of the leading edges of the main rotor, but it doesn't seem to be any more than typical with a Robinson blade.
Get some practice with brown-outs with someone who has experience, I deal with it on a regular basis. Like spinwing mentioned, no-hover landings are essential. Quick pickups as well, but you have to be smooth and clear your area/skids carefully. It is best if you can keep just ahead of ETL and make a quick/smooth touchdown, but that isn't always practical or safe, and inevitably you are going to end up in a brown out condition anyway.
I would share my methods on dealing with brown outs, but everyone has different techniques and I don't feel like starting that argument.
I haven't tried blade tape myself, so I cannot comment on that.