Marushin shell ejectors vs. STI

So is there a difference between the Marushin and ASI versions? Specifically like the Version II Marushin 1911 MEU currently up on Redwolf and the STI version recently/currently sold at more US airsoft sites like Airsplat? I really love the general design, but I've been sad at how weak the spring and blowback are compared to some of the comparably-priced gas blowbacks, which may be all-metal and much crisper.

http://www.redwolfairsoft.com/redwolf/airsoft/Gas_Blow_Back_Pistols_Marushin_Marushin_M1911_A1_Dual_Max_Ver_2_6mm_BB.htm

I have the Marushin ver 2. 1911A1 and it's much better quality than the ASG STI version that I bought at AirsoftGI. The ASG cycled terribly and the slide would get stuck halfway after ejecting a shell while going back forward. I tried to interchange parts between the 2 but I really think I got a lemon from ASG, since I've seen youtube videos of these that fire perfectly.