Before choosing the OnePlus One, beware of the shipping costs. This week they have released the phone to everyone, which means you may not have an invite to actually buy the phone. I have two reasons why I wouldn't choose the OnePlus One, right at this moment in time:
1) The OnePlus Two, or so it is nicknamed, is strongly rumoured to be coming out at Q3 of 2015. Meaning between July and September. If you do not urgently need the phone, I would recommend waiting a bit.
2) The shipping costs. (This may differ according to where you live). I live in Europe, and a friend of mine, had an invitation so he decided to buy it. Since our country is not listed as a possible shipping destination from the company he sent it directly to the UK and back to our country. The price totalled up to about $430. So I strongly recommend to calculate the total costs including any taxes you may have for importing from outside of the U.S. (or where you live).
EDIT: Since you're mentioning the Motorola Moto G (2nd Gen), I had that same phone, but got stolen after about 3 weeks. Nonetheless, a wonderful budget smartphone indeed for about $200. Great 5" design, poweful speakers, but slightly buggy camera. All in all, worth it.
EDIT 2:
Samsung Galaxy S3: Specs are way too old.
Samsung Galaxy S6: Way out of the budget, about $700, I believe.
LG G2: Great phone. But G3 came out 2014 and G4 is expected later this year.
(Don't mean to undermine anyone's opinion )
