Hello and welcome to the forums
Both are really good,the first one provides more Amps on 12v rail,whereas the second one is a modular PSU,so if you are OK with a non-modular PSU then go with the Corsair one,otherwise go with the coolermaster model
A quality 600W power supply can handle your system even with two 5770 in CF.
Anyway, If you can afford the price of a 850W unit, it's even better.
I would go for the CORSAIR TX850. This unit has been made by CWT, which is one of the best PSU manufacturers nowadays.
It's a rock solid power supply. All capacitors on this unit are Japoneses from Chemi-con. It has a good efficiency (80 Plus certification) and very good voltage stability (voltages very close to their nominal values) and excellent ripple and noise levels on its outputs.
The fan is a good 140mm YATE LOON D14BH-12 which is rated for up to 140.0 CFM at 2,800 rpm and 48.5 dBA at full load. It runs quiet but is audible at high loads (but it won't be your problem).
It has all the protections you could need and a 5 years warranty.
Don't get me wrong. The COOLER MASTER Silent Pro M 850W (by FSP) is a quality PSU, but the Corsair TX850 is better.
i have never used a modular psu
thats y i m asking which one can last longer
Both will work fine for a long time.
Going with a modular PSU lets you choose which cables you need and you can remove some extra cables that you don't need,and your case will be a little tidier,but if you are OK with a non-modular one then go with the Corsair.
Being modular or not has nothing to do with the quality. A non-modular PSU is not better than a modular one.
I prefer modular PSUs because you have less cables inside the case which improves the air circulation.
Switching cables is extremely easy.
I never said a modular PSU is better,i just said with a modular PSU the cable management will be more tidier,as for the difficulty,both are easy but like i said,with a modular PSU you detach the cables you don't use