The biggest regret was buying a Custom TM AK-47....the thing broke down every 1000 rounds... I repaired it 3 times by a very good gun doc and it cost me about 200 bucks...I ended up selling it for 750 which was much less than what I originally paid for it...
The previous owner was the 3rd owner and didnt tell me that. I was really new to airsoft at this time and the guy ripped me off big time.
Other than that I am very happy with my purchases, especially my RS and CA...great buys. Now that I have had a little bit of experience I have been able to find some better deals