Been to screwfix today an picked up a bosch grinder (600w) for £35, i have the same one at work its 10 years old gets used an abused everyday an its still going strong. Can't rate them enough grab 1 while you can
I bought a 700 watt Bosch pro angle grinder about 2 years ago in a similar sale, it has had a had life but still going strong. You can get a pack of 5 x 1mm discs for about a fiver there too and they appear to be fairly long lasting
The hitachi one I bought from there offer at £25 is a nice tool. Tbh it doesn't get much abuse as it spends 90% of the time with a 60 grit flashing off burrs. I'll let you know in 10 years.