Beginner here. Just wanting a little quick feedback before I pull the trigger. Not going to buy used for a variety of reasons, none of which I need to go into here. I've narrowed it down to these three.

• Budget: $400.00 US

• Gravity Avenue FXD. $349 http://www.bikesdirect.com/products/gravity/disc-brake-road-flat-bar/avenuefxd-disc-brake-bikes.htm

• Diamondback Sorrento Hard Tail. $380 https://www.amazon.com/gp/product/B0119ONAES/ref=ask_ql_qh_dp_hza?th=1&psc=1

• Trek 820. $380 https://www.trekbikes.com/us/en_US/bikes/mountain-bikes/cross-country-mountain-bikes/820/820/p/1008600-2017/

• Riding environment: Paved surfaces primarily, for recreation and exercise. Would go trail riding every once in awhile, primarily on easy-to-ride trails.

• My stats, if it matters at all: 6'1", 215 lbs.

With the first two, I would have to build them and pay for a first-time ride tune-up (REI 60 bucks -). The Trek would come from the LBS fully assembled. I understand that there is a benefit from buying from the local bike store, ie repairs, service, etc., so there's that.

All things considered, I'm leaning towards the Trek. Good call? Bad call? Are there other bikes in the under $400 category that I should consider?