My recopmmendation in a Green is Honda Type 2 antifreeze. It is a non-silicate formula, and is pre-mixed with 50% distilled water - you just pour it in, and do not have to worry about titration.
I have seen some Honda engineering studies of what silicates did to heads, water pump impellers, etc in their cars, and why they make a big deal out of specifying their coolant.
G-5's are excellent too (glysantins). My SVT Cobra* came with it, and they are long-life and very low abrasion.
The hassle can be that some combos of fluids will cause gelling, and even if you flush til the cows come home, the tuniest nooks and crannies of the radiator will retain some old fluid, and it is precisely in those spots where either corrosion or an accumulation of "glommed" varying coolants can occur, which at weorst can lead to diminished flow.
It is a good rule of thumb that sticking with what the mfr recommends is a safe bet.
*Ford used two coolants in production of the 2003 Cobra - a green, low silicate, and a yellow G05 glysantin. Ford spec'd the yellow (Gold) for 20K more service life. But they also stressed not switching from green to yellow, yellow to green, or mixing them, for the reasons I stated above.
Ford's G-5 is called Premium Gold and is fairly priced and excellent.