I'd say the Lauriepedals HZD is useful... the FA-1, not so much (barring a nice pedal switching system)..
Id say the HZD reins superior over that FA-1. Because of its price, usability and sheer awesomeness
I would have to agree with this sentiment 100%....i had the pleasure of being able to turn the marshall head up halfway on a gig the weekend(the rest of the guys actually asked me to turn up...)and the HZD boosting the front end of the marshall was SRV/Rory Gallagher city.......i could easily do a gig with the HZD on its own and the amp....this little box really loves a good old basic valve amp... and i could also easily understand why some people would want to leave it on all the time......