I'm a bit with Daniel (first reply) on this, and also with the people advising you to go to a club meet to assess various designs. Big dobsonian-mounted telescopes may be the go for established observers ("bang-for-buck"), but for anyone who comes along and says hey, this astronomy stuff sounds interesting, I'd like to get into it, then big dobs can be the hobby-killer. For a start, they're massive. How do I know? Well any non-astronomy person who comes into my house and sees my little 4.5" reflector sitting in the corner instantly says, "Wow, look at the size of that thing, it's huge!!". I then have to explain, no, it's very small!
People do of course handle big dobs easily, but the point is that they require effort. Not just set-up, dismantling and storage, but the big mirrors need to be
very accurately collimated (ie optics precisely aligned) before every use, and they need time to cool down. If you want to do some observing, allow an hour or more before getting your eye to the eyepiece. Beginners need something that they can just take outside and observe with.
There are a number of success stories on IIS about people who have taken the plunge with a big first scope, but this has to be tempered with the huge number of 'pristine condition, barely used' big dobs that come up for sale on IIS and other used astro equipment sites. Find out if astronomy's the hobby for you before going big.
The smaller Mak Cass telescopes like you were describing are good first scopes because they require little work or effort to use. The downside is the high cost. 5" is a perfectly good aperture to see an abundance of deep sky objects, including galaxies, nebulae, globular & open clusters. A member of our local club has a Meade 5" Mak Cass and it gives some brilliant views. However, be warned that you won't see objects as they're portrayed in long exposure astrophotography (neither will you in a 14" or 18" dob), and also remember that observing takes practise. First up you mightn't be able to discern objects that later on are an absolute snap to see. The mind needs training. This applies whatever the aperture, as fainter and fainter objects come within reach.
Other options might be a small refractor (80-102mm, achromatic), or a small reflector (114-130mm), both cheaper options. Collimation for the latter is not demanding as it is less important than for big mirrors. I check mine about once a year, and it's only required a tweak twice in 5 years despite some rougher than usual handling. Cool down time is negligible, takes less time than dark adaptation of your eyes!
Good luck in whatever your choice - just don't buy a plastic telescope! Go brand names.
Cheers -