H-Power E4 2-4S 30W LiPO/LiFe RC Balance Charger 1-3A
This is the charger I currently use for my 5000mAh LiPo batteries. It can be regulated at 1, 2 or 3 Amps, and for either LiPo or LiFe batteries. It is compact but looks well built and has some heft to it. My current favourite of the three different fast chargers I have.
The Xiegu G90 does not yield full power (20W) with the 3S LiPo batteries, so I am planning of building some LiFePo4 batteries to unlock its full potential. This charger becomes very handy in this case, and its versatility is not at the expense of complexity. Versatile and simple. The best of both worlds. Highly recommended.
I see now it is rated at 30W, which makes it difficult to yield the maximum 3A when charging a 3S or 4S battery. I haven't tested that yet but bear that in mind if you're going for the highest speed.