Ive had my eutech pctestr 35 for two years it cost me $220 . Ive calibrated it twice and it's just as accurate as the day i bought it. A good meter is an investment in your grow op. If you buy shit their likely to leak and you will end up drowning them and wasting more money, and you tend to look after something that cost money as well so if you look after them, rince them after use and clean with probe cleaner every now a again, try not to drop them and you be laughing. They will last you a life time. I also have a blue lab truncheon. Its good too bcause it gives me a ball park PPM reading and the eutech reads In E/C. Because you guys over the ocean there tend to use more PPM than here in OZ, we use more E/C. hope this helps don't forget the reps cheers mate and good luck.