I do own a Lonestar 1x12....
I'd like to say that this is Mesa's best clean amp, ever. I cannot imagine being happier with any other amp for the tones that I get out of this amp. And for the price you paid I think you'd be crazy to consider taking it back if you look at the WHOLE picture for the tones you are wanting to present while playing live or recording, (*not sure of your intent here so I'll speak on my quest for the ultimate amp).
No amp will do it all.
Just so we are clear let me repeat, No amp will do it all.
I had a Mark IIc+ combo with all the options, Simulclass, EV, EQ. I had both foot switches for it, the Lead/Rhythm and the EQ/Reverb. I used the EQ/Reverb switch to give me a Lead boost for either my clean or gain settings. And even with this so-called 'Holy Grail' amp, I was not happy. I could get a great metal tone that produced a shi++y clean tone or I could get a good clean tone that didn't push the preamp enough to get a good rock/crunch tone. I also used a modded TS-9 in front of the amp and an Intellifex through the loop, I still wasn't completely sold that this was the best fit for me. This was the second MkIIC+ I had owned that I had had for about 10 years, the other one I owned about 7 years, and I just wasn't happy with it. I wanted a good rhythm, clean and crunch, AND a good lead tone.
Long story short, I sold it and bought 3 amps to replace it, (*I'm also considering a 4th in a Stiletto or a Splawn and a 5th in a Epiphone Valve Jr).
If you want a Mark sound, you won't get it from a Recto.
If you want a Recto sound, you won't get it from a Marshall.
If you want a Fender sound, you won't get it from a Mark.
If you want a Marshall sound, you won't get it from....
I'm sure I could do this for a bunch more iterations but I think you get my point.
Now, playing live we as guitarists need WAY less variety from an amp than you would think if your intent is to please the audience. In fact you don't really need a good clean sound at all so you could get by with a great pushed sound and some processing and be there. By that I mean a good reverb and delay in the loop, a good chorus and some overdrive/distortion/compression pedals out front and you are there. That will cover your live setup. You may have to learn to tap dance but you don't need $15k worth of amp/cabinet/switching/processing to pull this off and it will get you 80% there. The rest of the band might notice if you had better equipment you recorded and/or practiced with but after the first few songs the difference would blur. Maybe the other guitarists in the crowd would notice, maybe not - it all depends on who's driving, not really the car or the race track.
Now for recording you are probably going to be a little more picky here but there are lots of tricks to get you closer to a sound than you having to buy a different amp to get you 100% of that tone that is in your head.
I doubt a RKII is going to be EVERYTHING for everybody but it is a great amp with a ton of options and covers a lot of sonic territory. I am not suggesting that you should consider NOT getting one but think of this.
If the LS gives you the clean you are looking for, look no further for a clean amp. For that alone I bought it because it blows away a Fender Twin, a Roland Jazz Chorus 120 and anything else I could think of for the price and you got yours cheaper than I got mine. (*I did replace the stock tubes and got an even BETTER sound out of it than stock and I was blown away with the stock sound in the store) If it doesn't that is another matter so why did you buy it? Answer that question and you will be half way to your decision of whether to take it back or not.
Tube amps are great when they work and a pain when they are having problems or need retubed. The RKII uses a lot of tubes and has some VERY advance features that you may or may not really need. Consider if you really want an amp that does everything it does in one package. Think if you want to have all your eggs in one basket, in case that basket is accidentally backed over in the parking lot by a drunken patron after a show.
Personally I still use pedals in front of ALL my amps because I use Good Low gain pickups in my guitar for the times I want the sound that only those pickups can produce. So I push the signal into the amp with a modded pedal, volume up/gain down, to make up for pickups that do not have a bazillion windings to my humbuckers or EMG actives. Just my preference here, YMMV. You might find this would get you closer with the LS to do the same. It won't sound exactly like a Recto but you could get close. Oh, and with EL34's, I doubt the RKII sounds like a Marshall or Stiletto either FWIW. I Love good Marshall tones, grew up on them. The LS doesn't/won't sound like a Marshall but neither will my Recto with different tubes or a pedal or EQ or ???, but I can get it close. (*see above comment about eggs and tones :roll: )
I hope this helps in getting you to look at all the options before you trade off the LS. Bottom line is you can ask owners of the RKII about the sounds but it really is up to you to decide as tone is subjective your hearing is going to vary from day to day. Speaker selection is going to make a huge difference too so try you LS with a 2x12 or 4x12 if you have one or access to these via a friend. Hey, drag it down to the store you bought it at and use cabs they have on the floor. Tell the salesman you are considering buying an additional cab for your LS. And for the record I have been a Boogie owner for over 20 years now, having owned many different models and playing just about every model in the stores as they came out.