I haven't personally lived in one but most, if not all, of my friends from school lived in various flavors of these developments. More importantly, my in-laws live in a nicer one (but ultimately still a development).
There are two flavors of developments, especially around where I live (mid-Atlantic).
Flavor #1 (my in-laws live in one of these) is a little pricey, but the houses are all not quite cookie-cutter. A lot of them have some semblance of character, and many are built to take advantage of the terrain of the lot. These are often ones where the houses are built over a longer period of time and by a mix of developers, so you get some stratification of houses as you go through the development which makes it feel less 'blah'.
Flavor #2 (most of my school friends lived in these) is basically a huge piece of farmland that's clear-cut and built out by one developer with about a 50/50 mix of 'custom' and out of the box homes from no more than 6 floorplans that generally all look the same. There's typically little to no uniqueness to terrain and the homogeny can make walking through confusing.
I have experience with both -
The cons, from my point of view:
-You'll be living in a construction zone for years.
-Until the saplings mature, the only thing you'll see is an endless field of roofs (about 15 years).
-It's entirely hit or miss who you live near. Some people are really great, and personable, and can make good neighbor-friends. Others can be reclusive or worse, standoffish and territorial.
-Depending on the land, you may be dealing with post-construction woes (foundation repair from ground settling, issues from construction, etc.)
-You have to drive everywhere, especially if you're more in the country (and 600 acres seems to suggest you would be) - there's no opportunity to walk downtown/to a park/to the store
-As time passes, the first wave of homeowners tends to not do too much with landscaping and maintenance, so in about 10 years the houses won't look quite as nice
-You will probably only break even at best if/when you sell
The pros:
-Standard building pros (you choose finishes/features, you have a better sense of the house and where problems could occur, you're the first ones in there so no weird stuff)
-You really won't have to worry about big expenses (roof, HVAC, etc.)
-It's super quiet, especially if you're not on the main 'artery' street
-Chances are high that other young families will move in too, and your kids can all grow together
I definitely wouldn't classify most subdivisions as shitholes, but they're also not for everyone. As you can see by my lists above, I wouldn't generally choose to live in one but it's really also completely dependent on location. If it's out in the middle of nowhere, then that's probably a no from me. But, if it's in an interesting area that seems like it would grow over time then I'd definitely at least consider it as a viable option.