Ok, before I answer this question... I would like to say that before I tried the siege I hated Brunswick. Why.. Well after 3 Wild Rides, a Maxxx Zone, and a TFD, I could not find one that I shot over 200 with. The maxxx zone burned up too fast for me, the wild ride was nothing like advertised in my hands, and the tfd was just like... ok. I made the plunge to grab a siege, and ohh my goodness. I have thrown all the big hookers (haha),and of the ones you mentioned there are some differences. I loved the mega friction and the VG was not too shabby either, the differences compared to the siege are listed below:
Compared to Mega Friction: More angular, less up front, more on the backend. Continuation through the rack is close between the two, but I can use my siege into the second game, where as the mf was put away by the 5th frame usually.
Compared to the VG: Very close to the same reaction in my hands. Both get good length, and then come out of nowhere on the back end. With that aside, my Vg's (I had a few of them) suffered reaction loss fairly quickly. I was resurfacing the vg every 30 games almost, and it never got back to the way it was out of the box. I clean my equipment after every shot, and before going in the bag, as well as using a ball spinner periodically to keep the surface up. If you bowl like I do (monday, wednesday, friday, and sunday), then that is like a resurface every other week. The siege has mainted its reaction very well, and to me handled carry down a bit better then the VG. Both are good balls, so it comes down to what you believe in. Put it like this, I just picked up a Wild Thing to give it a try because of the Siege!
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Hmm..Lets see what I have in this bag...some virtual gravity, some hot sauce, a liberator, and a saw.. how can I loose....
....HG-300(2006 w/Desert Heat)...299 (03/15/09 w/Agent Orange)...HS-776 (Hot Sauce Pearl & Ebonite Magic)