It just has more/longer drawers, so more rails/bearings/hardware, I wouldn't say more quality.
Bottom 2 drawers in the cheaper one each support 100lbs also, not sure how you'd put 100+ in any drawers above that to be honest.
I don't think its worth the extra $130 IMO.
2 more sets of slides/bearings aren't going to account for fifty lbs... same amount of sheet metal because they are similar in overall size.