018 has been known to give me anxiety. Definitely not my favorite. Though 250 feels like nugget to me much of the time. 250 will put me to sleep while 018 will get me high but can only smoke so much of it before it gives me a rapid heartbeat/anxiety.
073,081,WIN compounds and 250 do not give me the negative side effects like that. Will admit though, one can achieve a pretty funky buzz when smoking a lot of the synthetics.
Also JWH and similar do not give the pleasure punch compared to Maryjane while on benzos...