The question of assembly
The main reason I didn't make a whole lot of money selling new bikes is the amount of effort required in putting together bikes from the factory. If you're doing a good job then all you have to worry about is the wheels, the headset, the cranks and the breaks. Assuming the frame is straight to start with (I've had problems with that also from the factory too).
Generally new wheels from the factory are set up with the bearings really tight. if you're not set up originally with ground and polished surfaces then go ahead and ride them for a while (as least a month) and then take out the old bearings and toss them. I usually replaced them with grade 30 bearings loose. Sometimes you can come up with a pretty smooth set after that.
Luckily bottom brackets are a little easier to deal with nowadays. All the bikes I own( except my fixed) have got sealed bottom brackets. I have a tool that faces the B.B. so you can set up the standard crank so that it will wear evenly.
Next question? Do you like the way the gearing is set up? and does it have a "flip flop" hub ? On my "road bike" set up I have an 20 on one side and a 16 on the other. Lucy for me I was able to swap out my old Campy 45 front crank arm for another 39 had in stock. Some day if I'm feeling fast again maybe I'll swap it back.(sheepish grin).
Tomorrow I'm going to go look at recumbents. Talk about the other end of the spectrum I used to call the HPV group that used to hang out at my shop "the nerds from hell" there were great group of guys and soom were even pretty fit. Here its cold and dark so maybe I can get a deal on a new Barchetta (well new last year) If I decide to go for it I'll show you guys a picture.
About 20 years ago i used to own a Infinity recumbent, but the frame broke right at the bottom bracket and before i could get it fixed the only bike I had that could ride on the HPV club ride was my fixed gear. And I still had sew ups on it. It was a handbuilt Calvert track bike that had only been ridden once at the Alpenrose velodrome. The poor schuck that bought it got new, road up to the up at the top of the some of the steepest banking in the united states and crashed. I guess he broke his collarbone. So 15 years later he sells it to me for four five hundred dollars. It also came with two extra sets of wheels and various other stuff.
Good luck with your new "toy" and keep the brake at least on the front.
Mike Frye A.K.A. Frye Bikes