Victor wrote:after spending many valuable weekend hours in bike stores, i finally found out that flat bar road bikes are exactly road bikes with flat bars, with little difference to those with drop bars. This is of course only true for my measly price range of $1000.
That's not quite right and there is a lot of variation within flat bars too.
Basically, a full on racing bike is designed to have the rider head down, bum up in a very aerodynamic position and the geometry of the bike (the steering angles, seat to pedal angles, etc) are designed to provide the most efficient use of power in that riding position and to meet the requirements of riding in a very fast pack. Typically, a full on racing bike changes direction very quickly at the expense of stability.
Moving up to the more 'comfort' end of the drop bar market - this includes touring bikes, comfort bikes, bikes that are designed for more relaxed riding (such as the Specialized Sequoia). These still have the drop bars and often bars lower than the seat to get that aerodynamic position, but the geometry is more relaxed ie, the bike is more stable and hence more relaxing to ride at the expense of not being as nimble.
Then you get the most sporty of the flat bar bikes, and these are probably fairly similar to the above group with possibly the bars a bit higher. You don't get the lowered hand position of the drop bars but you still get that reasonably quick steering. They don't use the same frames as similar drop bar bikes though but can be converted if you are prepared to buy new levers and bars (gets pricey very quickly and isn't worth it usually).
Then there are the very relaxed bikes - these have the bars quite a bit higher than the seat and closer to the rider, so that the rider is taking more weight on the seat that in the above class. The geometry is more relaxed yet again - you have a bike that is very easy to ride and comfortable as you are sitting upright with your weight on your bum. However, that upright sitting position is not as kind to your bottom and you have to push all the air out of the way with your body - in a head wind, you feel like the mainsail on a man-o-war.
You need to work out where your riding use fits into the above categories, and that description is very basic - it varies dramatically from brand to brand, even the descriptions and names of the various classes varies dramatically, so I recommend that you read through a few of the websites/catelogues to get a feel for where you want to be.
As far as the componentry goes, I've never looked into it so I don't know how much of the flat bar componetry overlaps with the drop bar componentry. Manufacturers do tend to choose components depending on the job - my Trek520 uses an unashamed mix of mtb and road groupsets, but I don't really know what's used on the middle to bottom end flatties. Maybe your reading of the websites will help there.
As for recommending something - that's up to you, your use and your body. That's not a cop out because what suits you, won't suit me. However, once you start to get interested in specific models, ask here about them - with luck you'll find someone else who owns that model and they can give you some feedback on it.
Richard