MrMedic's a very dodgy software engineer to say the least, lol.
His DLLs pack more than just cheats. Depending on what mood he's in and what hack you're using, he'll either throw in A) a hard-coded "trial period" (after which the cheat menu will lock you out) or B) will just straight up include a trojan virus as a nice surprise post-injection. The latter is almost guaranteed if you're using a public release like his external autoblocker and aim-bot hack. If however he's in a particularly boring mood he'll just give you the wrong encryption key for the zip file and have the TKC mods ban you (after you've dumped his fees into his non-refundable PayPal account, of course). I'd have one of the boys at UC take apart the assembly for one of his hacks as evidence, but I really can't be bothered.
I'm not saying this to deter anyone from using his hacks; I don't care about comp in the slightest. But I do lay awake at night thinking about all the Turks and east Euros Medic has successfully swindled.