Festool, Bosch etc. are arguably a little better but these are extremely good value - they do the job and are a sound buy. I sawed through a scrapped threshold without seeing the steel bar in it and went through without blunting the rough work one.
Starrett are v.good. Most are M42 standard meaning they don't fail or blunt when you hit a nail. They are very accurate too. They do a very handy Wallet with a range of blade types in it which is very good value. I've had mine for 6yrs with good use and still going strong - never had a blade fail or one blunt so far.