Visited San Marcos for over a year, was an ok time till 14 Feb, then the unprofessionalism and temperment of the staff changed my opinion drastically. I am never going back and highly recommend jumpers (new and old) to go elsewhere. Most issues dealt with the tandem instructors...there were minor issues over the months, but I looked past those because the people that go there to fun jump are a blast to hang out with. Unfortunately I reached my break point a couple weeks ago. I took some buddies to go tandem while I was making a fun jump. Tom, one of the tandem instructors who is apparrently new, was a complete ass. I heard all about his father owning a DZ out west, but this guy seems to have picked up the skygod complex. He was doing tandem with my buddy who he yelled loudly to several times for not understanding the sequence of exit (by the way he never briefed my friend and first met him at the plane)...hey Tom, when tandems are going jumping they are usually highly inexperienced with no clue what is going on...bear with them. Same guy then proceeds to yell at me about my gear and how it is messed up and reaches over to disconnect my RSL while 'attempting' to help...my gear was actually fine till he touched it. I spoke with management about the above instructor and they pretty much blew me off. Other staffers seem to have similar issues, just lack of professionalism and customer service...they only see jumpers as dollar signs. The only exception is Sarah in manifest who is very sweet and tries to keep a straight head about everything. Overall I am done with San Marcos...I have had minor issues crop up over time but that last experience blew me away. DZ's need to understand that there is more than just money involved and that customer service and professionalism are huge. Even if you are on your 8th tandem for the day, you are still expected to still be courteous and respectful.