okay tomorrow will be one week and I've tried it with every guitar except acoustics and my baritone so time wrap up my thoughts on it over all.
1. using alone with the two watt amp is one of this amps biggest strengths, if you have a small cab (it does push my 4x12 nicely) and a place to mic up a cab this is imo the best 100% tube tone for the money. With shipping and the two watt power tube option it was $315.00, but because of it's flexibility as a pre-amp it's a better value than say the 20 watt jet city or picovalve though both sound excellent and I do plan on owning at least the pico and hopefully both...if I dont buy another Frenzel (more on that)
From true Fender tube sounds to Marshall (imo a little more plexi/bluesbreaker like than 800 but it does a nice 800ish tone) but the tones are quieter and have much more definition.
2. Front end for a soundcard
a) using a sim or similar it depends on how much fussing you want to do, I found in AT3 that the THD bi-valve model was the best match for it and it sounded great. When pushing hi-gain models it got too noisy from the sim, I found this too with VANDAL, VANDAL on the clean setting with this in front of it sounded awesome but with both AT and VANDAL that meant going without stomps or much gain from the model used (or in VANDAL's case which doesn't have models, from the amp).
b) with an impulse loader or speaker sims it really is just as good as mic'ing a cab. KEfir and Poulin with acme impulses are just fantastic. (I like the latter better) Using AT, GR, GTR and VANDAL and bypassing the amps, just using the speakers and mics is pretty good but less than practical in some cases. GTR and GR even with the the control room fall short of both VANDAL and AT for this, those give you much more choices on mics, position and such. An interesting surprise was the speaker sims in the emu power fx sounded better than average, not quite as good as impulses and not as good as mic'ed but for sure a good way to work late at night because the emu is in my monitoring section as well as recording so I can record it with and without the cab sim while still taking advantage of direct monitoring.
3. Like a pedal for my amps, I kind of went into to detail on this already but the bottom line is it works well but you can't hit it with a ts or od without some unwanted noise. Pushing the egnater power amp was just as expected but not quite as tight as using it's own little power tube. Of course if you put it in front of a clean amp you get some great tones.
The variety of tones no matter how you use it depends on a lot of things, with some kind of od on it's own it's one of the best sounding amps I ever played through. The dynamics are stunning, from a a quiet subtle passgae to ripping power chords to biting solos without adjusting anything besides your attack, palm muting and such.
I would surely order another amp from them and have my eyes on several, the 'Sweet Little 15'
595 usd with the cage and 100 less without it
15 watts, tube rectifier two channel if you use an aby, class A power section
'HB-WC30 "Hot Box Wild Cat 30' 695 usd without case or cage, 795 with steel cage
30 watts, two channels (aby of course), tube rectifier, class A power section
If I had the money I would not think twice about it and I also am considering the other pre-amps (that also have the same 2-watt option I have) starting at 385 with the two watt option.
Really fantastic amps, but next time I'll expect 2-3 months for a wait