The Zero,
www.clasezero.com

A design by Lombard, one of the most succesfull mini designers lately, with Manuard Finot and Magnen. Based on the 240 . Build in Spain. It is now the second or third (i do not know the sales number of SuperCalins) most populair design still build (think Pogo1, not build anymore, lots of them around though).

A fast and strong design, with some twists, lifting keel for easier transport, the most deep cockpit and the only one with closed stern (more expensive to build). Together with the Pogo2 it has an entrance under an angle, making going in and out the easiest on thoose boats.
Large sidedecks, with a slight step in it, means a dryer bottom. And it has wings, little flaps sticking over the cockpit, if your head is not to big, it can protect you from wetness again.
More noticable are the two big windows, making it very light inside, and you can see the sails from inside. It has 4 winches, some say overkill, other say, damn handy. This is due to the entrance. Other easy to spot difference is the mast, it has a full width top spreader. Gives a more stable mast section in the sideway. Build with old fashioned bulkheads, so to decorate the inside is easier, but very handy for making storage areas. See build method later on...

Off course, this boat is a compromise too, with the liftkeel comes a deck stepped mast.
In case of mast breakage, likely the whole section will drop of. Hence detail to strength and the use of full width spreaders. But mini masts tend to do drop total rigs in general, even keel stepped masts.

The liftkeel; if designed right no problem, and Lombard did his best, even if bolts fail, the keel will wedge itself stuck. This is something the Zero yard does not want to show off to much, as it is a neat trick. One hint, top of the foil is thicker then where it sticks out of the hull. Is it waterproof ? This keelsystem asks for a structure higher inside the boat then normal, that makes it much easier to make watertight, and stronger, the keelbox is laminated to one full and one 3/4 bulkhead. And it makes a table or seat. Standard it comes with a bare metal plate, cover it to make it look nicer :)

The Zero is in between the Pogo2 and Pogo1 in the hullshape in the back.
As the Pogo1 was a heavier design, and of older ideas and material build, they made it so round (its an 90 design). Then the P2 came out with a very wide aft section.Makes for a better downwind performance was the thought, but actualy reaching it helped the most, downwind is anyway all up to skills of the sailor, a bit wider ass (5cm) or not is a small area.. But in rougher cross seas you get tossed around a bit more, translate this to the mast and sails, you loose speed... So the Zero is in between, not to extreme, but not skinny. If you look properly, only in the very last part and around the waterline it curves back. So less wetted surface, but less planing surface too. Due to the rigging the Zero can hoist a bit bigger genua, so it wins back there. Its all about optimalization of your design...
(Note, i use slightly, bit etc, the performance differences are hard to measure, in short runs, the Zero,Pogo2,Ginto and Dingo where very equal in speed. Its really up to the sailor to get up to speed.)

Usability:,
Due to the deep and closed cockpit, higher cabin top, wings over cockpit, this design is very good for colder water areas, and in rough seas (the hull shape helps there too).
The coachroof is higher then other designs, due to getting the keelfoil inside for lifting, this makes it very roomy inside, with big windows, its a palace compared to protos. Expect to get a lot of other minisailors onboard when it rains and the bars are closed.
The runners are placed wide on the outside, makes gybing and tacking way easier then if they are very close to centerline. Close to centerline is better for the masttop.

One thing the Zero differs in too is the cockpit is designed for two, max three people. So if you plan to race with four, you can like the other boats better. This due to the large cockpit box/exit in the back. But it gives a good footrest. And enough space for improper launching of the liferaft inside the boat, what has happened :)....

Building with full blown bulkheads. This is on the first impression heavier then no bulkheads, but gives it a very strong backbone, no flex in the deck etc, it gicves a strong and robust feeling to the boat. Do the jump test... As Lombard specifies Unidirectionals and Biaxials in the hull layup, this saves weight over the rovings and mat other polyester boats have used or are using. Due to bulkheads the hull can be a bit lighter.
 If you have not a bulkhead under the mast, you need serious reinforcements (adds weight) in the grid you use, otherwhise your boat will be pushed smaller due to rigtension (partly the reason why the bulkhead less boats have the rigging not full width, while every proto has full width (except rotating masts) as they all have bulkheads too, but out of carbon and nomex more likely).

A bonus of the bulkheads is resting, look at the guy sitting, if that is where you sleep while sailing alone, you are in between two bulkheads, if the boats stops, you can not move far, sleeps much better.

Oh, and for the bigger guys and girls, the back hatch in the stern is quit large. According to the rules, you must be able to crawl out there, can be a problem with some other designs...