nextar.comは安全ですか？

no one here speaks english. i bought a unit Jan. 08, have had to have them ship me 2 more because the previous 2 malfunctioned. both times they did not include required chargers/mounts. it's been 2 months still waiting on the last charger. i can't wait to get rid of this thing! (the GPS system M3-02) Poor customer service, also, they CHARGE for map upgrades. and they require you to pay shipping on returns with no reimbursement. They also would not just give me my money back because they said they 'can't'. Please don't buy from nextar, they will just give you the run around till you give up.