Modulating ductless VRF (mini-split, multi-split) can be really great from both a comfort and efficiency point of view, if carefully sized for the loads. The very high SEER units will have pretty lousy latent load handling in normal cooling mode, which is a serious drawback in your neighborhood on the stickiest of days, but they also have a "DRY" mode to boost the latent/sensible cooling ratio.
The turn-down ratio of VRF air conditioning really matters. The most common mistake is oversizing the equipment for the load, often to the point where it rarely (if ever) operates in a high efficiency maximal-comfort modulating mode, but instead cycles on/off. Design the house carefully to minimize the peak sensible cooling load, (=minimal west facing windows, no ducts outside the thermal & pressure envelope of the building, high SRI roofing materials) but then be aggressive pn the shading and R-value factors for the Manual-J load calculations. Having modulating equipment that is so oversized that it rarely modulates sort of misses the point. The oversizing costs more up front, and provides lower comfort & lower efficiency forever after.
With some careful design tweaks (download BeOpt, and learn how to use it), you should be able to get the design cooling load of a 2000' house down to the 1.5 ton range or lower, though most HVAC contractors will swear that it'll need twice that or more. See the house size vs. square feet per ton graphic drawn up by Allison Bailes, a consultant in the Atlanta, GA area:
http://www.greenbuildingadvisor.com/sites/default/files/images/Bailes%20graph%20for%20Manual%20J%20blog.preview.png
For the whole article, see:
http://www.greenbuildingadvisor.com/articles/dept/building-science/manual-j-load-calculations-vs-rules-thumb
or
https://www.energyvanguard.com/blog/air-conditioner-sizing-rules-of-thumb-must-die
This was a range of existing houses, not specially optimized high performance houses, most of them in the gulf coast states, at the 1% outside design temperatures (wet & dry bulb) for those houses. A house optimized to limit the peak loads can get it down to a ton per 2000' or better.
If you oversize a VRF that has a 3:1 turn down ratio by 2x (common), you're robbing yourself of comfort, and paying for it. If it has a 10:1 turn down ratio you'd be fine, but a more typical range for 1-2 ton systems is 3:1 or 4:1, eg:
https://nonul.mylinkdrive.com/files/SLZ-KA12NA-SUZ-KA12NA_Submittal.pdf
A mini-ducted unit might be preferable, for better heating/cooling distribution, but most multi-head ductless systems won't modulate below a half-ton of cooling output, and multiple heads would be oversized for their zone/room loads. The 1.5 ton Fujistu 18RLFCD has about a 6.5:1 turn down ratio in cooling mode, and can modulate down to 3100 BTU/hr, which might be a good choice, depending on layout:
http://portal.fujitsugeneral.com/files/catalog/files/18RLFCD1.pdf
With Mitsubishi the 3/4 ton and half ton single ductless mini-splits have huge turn down ratios, and a pair of them would come in at the same minimum modulation as the 1.5 ton Fujitsu mini-duct unit, if your floor plan can work with just two point source cooling units:
http://meus1.mylinkdrive.com/files/MSZ-FH06NA_MUZ-FH06NA_ProductDataSheet.pdf
https://nonul.mylinkdrive.com/files/MSZ-FH09NA_MUZ-FH09NA_Submittal.pdf
Note, the nominal 3/4 ton FH09 has a maximum cooling capacity of 12,000 BTU/hr (= 1 ton), but is efficiency tested and "rated" at 9000 BTU/hr. With 12K max, 1.6K min it's a turn-down ratio of 7.5:1, which means it'll run nearly continuously and super efficiently, if matched to a 9-10,000 BTY/hr peak load on the zone.
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