As a weaker player compared to the players that would play in this event, alternate break is the way to go. Get many more chances and tries at the table, and for only $500 entry. Only the Elite players are going to do $1000 entry winner breaks.
On the other hand, the Matchroom US in Open in April, with winner breaks and $1,000 entry fee, had filled its field of 256 a couple of months in advance of the event and, consequently, had to turn down countless people who sought entry into the field. Both the US Open 9-ball and the International are elite events that are WPA sanctioned and offer WPA Ranking points. Each event has very high prize money.