Right, so some time ago, I wrote a testimonial for the cheat, and at the time, it worked well, but I've had to re-evaluate my review a bit.
Aimbot - 6/10 - While there are still ways to work around it, and manage it, the aimbot is bad for any gamemodes like Nutscript and Clockwork. It works flawlessly for gamemodes like Dark RP, and as long as you don't go too crazy, it's typically alright for detection; though, it can be blatant if you're not good with configuration, but that's really any cheat. Despite numerous complaint threads and testimonials, there's been no real effort to fix the aimbot for roleplay game-modes, and it's effectively just a sloppy fix that locks your viewangle in place and prevents you from moving your mouse when holding the aimkey down. This is both parts blatant and difficult to work with. Don't buy for the aimbot, if you intend to use it on roleplay servers. Dark RP and other gamemodes, this typically works alright.
ESP - 8/10 - The ESP can drop your FPS, but if you have a good enough graphics set-up, it's barely noticeable. As far as functionality goes, the ESP and walls are fairly reliable. They're customizeable and have plenty of options to fit one's individual tastes. Definitely a solid ESP, but there should be some FPS tweaking to get a bit further along. I'm not an expert on that, and don't know how you'd do it, but the FPS drops have made the cheat a bit hard to work with at times.
Stability - 4/10 - Major points docked off for this. Though it isn't all the time like it was before, Citizenhack is tied very heavily to your network speed and stability. Even momentary lapses can cause your whole game to crash, and even if you don't have a lapse in internet, sometimes it'll just decide to throw a fit and quit on you. It isn't nearly as bad as it used to be, but there are still lots of crashes. It's a good cheat, in that respect, but I don't recommend it if you don't have reliable internet and a PC set-up.
Detection - 9/10 - I've rarely ever been broken when using this cheat. Detection is a solid point, but even now, servers have specifically developed anti-citizen cheat detection. Of course, the number of servers with this are minimal at best, and aside from a few meaningless TTT servers, the main server with this is Requiem. This is another server that ties back to my complaint about poor service with roleplay servers, specifically in Nutscript and Clockwork. As long as you avoid certain servers that specifically look for Citizen, you should be fine.
Staff Support - 5/10 - It's pretty much a hit or miss as far as staff goes. You can either get great, reliable help, or you can get a patch that'll fix it for about a week. At first, everything was reliable and solid, and then, the whole roleplay server thing broke Citizenhack for a week. After about two months of being broken with no word or support, we got an anchored viewangle setting that butchered the chances of hitting a soul with it. For just about anything related to the settings, staff are reliable, but updates to the hack shouldn't be expected frequently. CH only seems to get updated in the case it near-completely breaks, but as far as helping you with configs, it's a reliable support system.
So, TL:DR, if you're buying it to use on anything except TTT and Dark RP, consider it more in-depth. If you're buying for a basic gamemode, go ahead, but I can't recommend the vanilla cheat for use with any detailed schema.