I've had the LV Xen and Xeo, and while I thought they were great when I got it, realize that the Petrel wins hands down. Before you buy a Xen or Xeo, have a look at the battery holder and the wires. Go to their manual on the website and read the paragraph on changing the battery. It is extremely important that you be very careful when you change the battery and not put any stress on the wires. While exercising caution, after 2 years 5 months, the wires became disconnected with the circuit board under the potting gel. LV CAN'T repair the unit, rendering it useless and I was SOL. As the unit chews up batteries like crazy, this is a big issue. This is a huge huge weakness in the LV design. So with a dead Xeo, I followed all my dive buddies and went with a Petrel. Uses a simple cheap double AA battery, and the screen is easier to read underwater than the LV - and especially easier to read on the surface in bright sunshine. Honestly, I can't think of any advantages that the LV has over the Petrel. PS: I have LV batteries, rechargeables, charger, and interface for sale. PM me if you are interested or look at craigslist Vancouver BC. By the way, do a search on SB for LV's and Shearwaters for sale and it seems there is a lot of LV's people are unloading.