I wear purple gear in all my slots 90% of the time, it is perfectly itemized for defense/shield and I am able to tank 3-5 players my level because of my gear. I have been doing this all the way to 35, and I have purple gear crafted 3-4 levels in advance for myself. If you feel like being powerful all the way up then synthweaving is very useful. To equal my purple gear, you'd need to fill all of your mod slots with purple mods, and you'd need to go to two different players to do that. It is much, much easier to have great gear as synth.