I have to be real careful to make sure when I give an opinion, that I do it in a way that makes clear it is only an opinion
That said, I want to explain that in the last two and a half years I have shelled out in excess of $6,000 on bikes and equipment, for my daughter and myself, and it's about to get worse. (As my daughter prepares to get into road racing) Of that amount, I consider I wasted nearly $3,000 or more of it. Almost straight down the drain because of products being 'grown out of' (and not in the child sense, but in the skill sense) too soon, or being deficient. It's because of this that I have strong opinions and voice them, but I also realize they are often mine alone. (Sadly, so Sadly
So, the reason most anyone on a road bike or good mountain bike cautions against investing in a hybrid is because of weight and comfort for the long haul. The thing about this incredibly addictive sport is that once you are hooked, that's it, you won't go backwards - only forward. So a rider that thinks a hybrid that weighs in at 30 pounds is light and comfortable might not think so when their skill and fitness level improves to the point where they are consistently riding a minimum of 20 miles at a time. Same thing goes for my earlier comments on buying bikes at Walmart and such. Sure, they work for a jaunt around the park or a spin through the neighborhood, but those components are simply not designed to last the way, say, the Shimano 105 components on my current bike went over 4,500 miles of hard riding before the first of them needed to be replaced - that being the shifters.
I have given away first two Sears bikes just a month after buying them (Sears was still selling bikes up until a couple of years ago, which is when we started riding - oh, wait, perhaps there is something strange about their discontinuing selling bikes when we started riding? YIKES!) followed by a Trek 700 and a Trek 7200 from our next round, and even now we have a Specialized Sirrus for sale (too much money into it to give that one away, but even so it's going for $.35 for every dollar we paid for it - more loss!)
I am sharing all of this because cycling clearly represents a lifestyle change of enormity and I hope that just one of my opinions might help some other aspiring rider not to waste as much money as I did. Riding five miles today will quickly turn into your first half or entire century if you ride regularly. Also, one of the real benefits of cycling is that it is VERY social, if you want it to be.
There are group rides in every corner of the country and they DO NOT require an invitation. Karen is right in thinking the socially-paced rides will usually require that a cyclist be able to maintain a 14-15 mph average speed for 20 to 40 miles, but you simply cannot imagine all of the new people that cycling will bring into your life this way or how soon you will be ready to do this. Some stores, even the famous Richardson Bike Mart in Richardson, TX, (largest store in the US and where Lance Armstrong began his career,) host beginner rides to help you get to the point where you are ready for larger, quicker rides. Sure, anyone can get on a bike and ride and get tremendous benefit from it and sometimes just the solitary act of spinning my heart out alone and with no distractions is highly satisfying, but don't brush aside the possibility of social rides as well because of the fun and companionship they will afford you.
Absolutely no one needs to spend as much as I foolishly did. I know cyclists that do every group ride for miles around on bikes that were ten times more affordable than mine, because they were careful and bought used, etc etc. Guess that makes me the biggest fool in the universe and for everyone else's sake, I hope no one feels the need to challenge me on that !
Allez Y'all - I'll shut up now