Catalyst Destroyer. It beats the Caldari Destroyer because it has more low slots allowing for more damage boosting modules.
This is the cost:
Catalyst 656,004.83 isk
8 High slots: 8 Limited Light Neutron Blaster I @ 10,001.18 isk each = 80,009.52
56 Caldari Navy small Antimatter @ 505.58 isk each = 28,312.48
3 Insulated Stabilizer Array I @ 10,004.02 isk each = 30,012.06
Hobgoblin I drone @ 2,708.06 isk
Insurance Premium: 155,561.4 (Platinum)
Insurance Payout: 518,538
Total loss after suicide = 434,070.35 isk
Prices are based on top buy order at Jita.
According to Eve Fitting Tool with perfect skills the ship puts out 276.6 dps with a 721 alpha. That's before over-heating and not counting the drone. Also if I had perfect skills I could fit a warp scrambler on just to make absolutely sure of the kill. It should be enough to take out an untanked hauler in most areas of high sec.
You also lose Security Status when you attack someone.
The basic plan is to two-box. One alt has a cargo scanner and a ship scanner, tractor beams and salvagers. When I find a suitable candidate the Catalyst goes in and the alt scoops up everything that drops and salvages both ships.
The reason I'm doing this is because a friend is coming to try Eve again having been rather bored in the past. Hopefully he'll like suicide ganking. Maybe we'll get a plex :-)