I have some of the Tactical Innovations TI-25 mags. They are AWESOME!
Some people shy away due to the price but they are fully adjustable in every way and tear apart easily for cleaning.
+1 on the TI mags. They have a polymer version thats less expensive than the all aluminum one. These have worked very well for me.
I have used the Eagle 30 rnd mags for years with no problems, Just recently started using the Butler Steel Lips and so far no problems.
The Butler Creek steel lipped mags are VERY well regarded.
-J-