I have had the Lunar Solo for about 5 years now.
Pluses: It packs small, about the same size as a small loaf of bread, it'll fit in the side pocket of my Gossamer Gear Mariposa backpack. It's light. It has enough floor space inside so that you never need to leave your backpack outside the tent unless you want to (because, say, it's wet). The vestibule is big enough for most backpacks. It keeps you dry in the rain and is fairly weather-tight. The side-opening door makes it easier to enter than the tunnel-type tents -- backup, plop your behind down on the sleeping pad, take off your boots and shove them to the right under the vestibule, pivot, recline, you're ready to zip up and go to bed.
Minuses: It's a PITA to pitch the thing -- it takes six (6) stakes, each of which must be the 10 inch Easton stakes because to get the canopy taut the canopy must be pitched floating about four inches off the ground, and it takes a lot of re-staking before the canopy is pitched correctly. Headroom is almost non-existent -- the only place there's any headroom is right under the peak where the pole goes up. Expect to brush the (damp) back of the tent when putting your jacket on in the morning. If you pitch it low (staked against the ground) because of bad weather, it flaps and headroom becomes especially minimal. It takes up a *huge* amount of space due to the massive overhangs on all sides of the floor tub, massive overhangs that make it especially weather resistant but makes the tent take up more physical space than my two-man Eureka car-camping tent. Forget about pitching it on a slope... it doesn't like that at *all*, you'll never get the canopy taut.
It is shelter, but annoying shelter. Frankly, I don't think I would buy the Lunar Solo if I were buying today, I would look the competition:
* Gossamer Gear's "The One" if I was willing to risk the ultra-light and expensive spinnaker fabric,
* The
Lightheart Solo, which is basically an updated and somewhat enlarged version of the silnylon tent that started it all, the Wanderlust Nomad. It's fairly easy to pitch, stake out the head, stake out the foot, get in and put in the poles, restake the foot to tighten the pitch, stake down the sides for wind resistance, done. It is, however, 11 feet long (!), due to the fact that Heartfire took out the spreader pole that Wanderlust used to make more room at the head of the tent, and instead just made the tent longer.
* The Tarptent Moment is fairly compact and needs no hiking poles to keep it up. It's especially easy to pitch (one stake at head, pivot until find place to stake foot, one stake at foot, then guy out the hoop to two more stakes or rocks or whatever -- note that you *must* guy out the hoop or even the slightest wind will flatten the tent). There's a Youtube video of some guy putting it up in less than a minute.
The Lightheart is about the same weight as the standard Lunar Solo with the heavy floor, "The One" is about 10 ounces lighter but you have to add another 5 ounces for a ground sheet because its super-expensive ultralight spinnaker fabric floor will just shred on normal Sierra surfaces. The Moment is about 5 ounces heavier than the Lunar Solo, but remember that it doesn't need hiking poles, so if you don't normally carry hiking poles it's actually lighter than packing poles just to hold your tent off the ground.
Hiking poles required: The One: 2. Lightheart Solo: 2. SMD Lunar Solo: 1. Tarptent Moment: None.
If you're a two-pole guy, I'd suggest looking closely at The One or the Lightheart Solo. If you're a one-pole guy, look at the Lunar Solo or Tarptent Moment. I'd probably choose the easiest to erect of each of these pairings -- i.e. the Lightheart Solo or the Moment -- just because the SMD Lunar Solo has annoyed me so much over the years with how frickin' difficult it is to get a good pitch in the kind of uneven terrain that I'm often having to pitch it in.