Id hate to directly put things down, but those two buggies are majorly outdated, and with serious price-drops on competition buggies these days, you would be stupid to buy one of those old Ofna's. They were good machines in their time for sure, but compared to offerings today, they will break parts, and wear out their drivetrains fairly quick.
I'd reccomend a GV-Rex/XTM Xterminator, or that lightning (fix a few things, and thats a real sweet kit) - even if the parts are a bit hard... parts are really important, but i'd be more worried about breaking things all the time on the ol' ofna's.
I guess if parts are abundant for the Ofna bugs there, the MBX/LX might be smart.... but even then i'd try to go for a hyper7/9.5 - they are so much better its not funny.
Don't get me wrong though, if you are generally nice on your kits, the LX/MBX should be fine. The pro versions of each are just cheaply hopped up versions of the originals - MBXR2 and GTLX, and comparing those, I'd say the MBX is perhaps better.
If they are in the same pricerange as a Lightning though, personally id have the lightning over them anyday.
jmo
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