-- Last Updated: Jun-21-12 9:06 PM EST --
Given your size/weight, you'd likely do better with the Fathom LV than the Fathom. I would check out that one and the Eddyline Samba.
In answer to your question, "LV" for lower volume can mean different things to different companies. For some, the hull is identical in terms of length and width, but a lower volume kayak will have a somewhat lower deck (less packing space, but if you're a daytripper this may be all you need). For others, including Eddyline, LV is a slightly shorter, slimmer version of the larger kayak. The LVs are designed for small-medium paddlers. The larger versions are designed for medium-large paddlers. (I'm in the medium range and can go either way.)
The Fathom LV is a fine boat. It is narrower than what you're used to, so it may feel a bit tippy at first, but once you get your sea legs under it, you will find it to be both fast and maneuverable, and it tracks well with the skeg down.
The Samba is a slightly smaller boat than the Fathom LV, similar in general concept. At 13' 10", it's lighter (which can count for a lot) and more playful than the Fathoms. A little wider than the Fathom LV, so a little less tippy. I have one of these and like it a lot. I have thought of getting a Fathom because the additional length translates into more miles covered for the same amount of paddling, but since I mostly do solo lifting and hauling, the reduced weight and bulkiness are very appealing to my middle-aged back.
Build quality of Eddylines is very high. Given a choice, be sure to get one with a back band, which is much more comfortable than their rather hard seat back.