I have lenses by Sigma, Tokina, batteries by energiser, calumet.
I will only ever have a speedlite flash by canon.
Why? Heres why:
Ease of use. A novice can clip it on, switch it on and get decent results.
Integration with camera menu. Including custom functions etc.
Easy Wireless control where supported.
Flash modelling preview.
Works properly wirh e-ttl pre-flash metering.
Works properly in hss mode.
Works properly in 2nd curtain mode.
Zooms with your lens correctly, even taking account of sensor.
Decent Af assist.
Future compatability with your next canon slr.
A cheap flash is like a cheap tripod. Fine for very very occassionnal use with low expectations, a false economy uf you are in anyway harnessing the power of flash.
I have a 430ex and it's a good balance of size weight power features and cost.
I could sell it for around 60% of what I paid for it 6 years ago, my 6 year old body would get around 20% of its original value.
Don't get me wrong, I also have a cheap fully manual ring flash which gives me great results within it's design specifications and intended purpose, but if you want a speedlite you really want canon.