I know there are a lot of threads about this amp, but I wanted to keep it out of the "hyped" threads and offer up some of my individual opinions. I am trying to be as objective as possible here, but my first impressions are this is a great little amp. The Shuttle is my first Genz-Benz purchase and as my expectations were high, this thing definitely delivered for MY needs. I AM NOT AN ENDORSER OF GB PRODUCTS. To give you a little background about me as a player and my tone goals, my main rig for the last two years is a DB750 through a large cab of sorts. (DB410 SA410 HT322 SVT810) I have performed the telefunken JJ tube swap to try and achieve a little more sparkle. However, the best bass tone that I have heard in my head, came from a Sadowsky SA200 through a SA410, all knobs set to 12:00 except for the gain knob set a little past 1:00. While the Aguilar DB750 has a great tone, it does not deliver my "ideal" tone. I play a lot of gigs in smaller venues where a 410 is too much so I have been on a quest for a lightweight rig for a while. I have not found one to my liking, but I have owned an AG500, Little Mark II, 70's WWamp and I ended up settling on lugging my DB750 around with 1 or 2 Epifani UL112's. I do like the WT550, but I don't love it and couldn't really justify owning it. Dragging around the DB750 is rather inconvenient for a lot of my gigs, but at least I could be happy with my tone. My main problem with the lightweight stuff that I tried, is that I felt like there was always a lack of perceived "thump." I am not a fan of the LMII and have done many gigs with that amp. However, I can see how someone who wants a really responsive sparkly high amp would love it. I received the STL 6.0 today from UPS. Right away, I found that this thing is not nearly as dainty as the threads seemed to infer. Everyone talks about how light and small this is, but it isn't much smaller that the LMII and doesn't seem fragile. This is a very solidly built unit, and screams of high quality components. I really, really like the perceived sturdiness of the knob and pot design. The test rig was a Epi UL112 with a Jazz bass with Sadowsky Pre and PU's and a Sadowsky M5-24. Since I like a warm sound, I initially set the gain until slight clipping began, and started with everything flat. Okay, this thing is loud, but it wasn't obscenely loud. However, I have not heard my UL112 put out as much discernible low end with any other head. So yeah, it thumps. I played blissfully, for a while and then got into the tone shaping. This really displays the versatility of the amp. With the low boost engaged, just make sure you have enough speaker. I can see this being great for switching from a rock song to a reggae/dub song with one switch. I tried to get what I consider a fast/ quick hifi tone out of it. (think TF550) This took a while. I was about to get discouraged, an then I found that the mid scoop switch engaged with a little bit of added low mids achieved this tone. However, it is my opinion, that it still wasn't as "sparkly" as the LMII. I personally love what the tube front end does in this amp. The tone that I can best describe is imagine a WW with a nice tube pre in the front end. (U5 Ditto) Pro's Sturdy for its size Tone ready to go, with all knobs at 12:00 WARM, WARM, WARM Loud and Full. (fills up a lot of space) Tone shaping controls make dramatic changes in tone. (versatility) This can also be considered a negative. (see below) Con's For me, it really doesn't have any, but since I'm trying to be objective here goes. If I wanted a lot of tones out of this thing, I would have to turn a bunch of knobs and flip a bunch of switches to come up with my desired tone. Personally, once I start a set, I don't like fiddling with my amp and prefer to vary my tones based on technique, hand positions and touch. Backing off the gain and increasing the volume doesn't really "clean" up the tone as much as I thought it would. (again, not a problem for me) EDIT:2/24 After two gigs, HiFi and sparkly tones are achievable. Rather than delete some information, my initial impression, is still my initial impression, but if you read on, after a few gigs, I figured out some ways to utilize the amp's versatility. (End Edit) IS THIS AMP THE BEST THING SINCE SLICED BREAD? IS IT THE BE ALL END ALL OF LITTLE AMPS? Ummm.... For me it is. It won't replace my DB750, but then we'd have a real problem in the bass world. However, I can very easily see how someone who loves their LMII will not love what this little amp does. I am leaving for a gig right now, and have three more in the next four days. I will have much more to contribute once those are done, but so far, thank you Genz Benz for delivering a little amp with some great booty and punch.