Not always best.... Everyone has different opinion about BB.
For example, my friend never hear other brand like AT&T Tilt or Nokia E62 or Palm Treo or other brands. He think only two (Sidekick and Blackberry) great for deaf. He gave me hard time to discuss.
Your friend had problem with SK1 to SK3. Do not blame Sidekick. Maybe, your friend at wrong place like weak signal coverage at country. She has to understand about tech of signal zone. Voice and Data are not same zone.
Dark green area is best signal.
Grey area is poor signal or dead.
If, I use Blackberry or any brand at very country in Montana/North Dakato/South Dakato. No way to get any message or send.
Even, I am at heavy wood/forest park in New Jersey. Any smartphone still not work at all.
At work place inside building, my co-worker has Sprint Cell Phone is dead. He has to go outside from building. It work. Other co-worker has Verizon Cell Phone still good work inside the building.