Thoughts on their claims? "After much R&D with the circuit we are proud to offer our FX8 Modification Service. This unit comes complete with our modifications service and is in excellent condition with original owners manual. The software has also been updated to the most recent version as well and is ready to rock! About the Modifications: We evaluated the circuit and concluded that while the effects sound excellent there is a fair amount of tone masking that still occurs in these units with low headroom and a fairly muddy tone. We also concluded that there was a pretty obvious low end hype that made instruments sound "more analog" but also a bit tubby in the low end. In addition the headroom is pretty low when paired with a Tube Guitar Amp. Good headroom and dynamic range are the main reason we chose a tube amp after all. For the purists who want the absolute best from this design, we offer a wonderful modification service that addresses all of the I/O audio path from the Send/Return to the pre input sections. The modifications come out sounding warm and musical with a non hyped sound that is clear, clean and has excellent headroom and dynamic range. The tone comes forward with the modifications as well where you hear your amp as if the processor where not in the loop at all. While these units offer a "True Bypass" it is really only a true bypass of the converters. The line amps are still in play so "Tone suck" Still occurs even when bypass engaged. The modifications address this as well for the purist tone possible. With the upgrade we change out all of the audio amps in the circuit as well as the capacitors for tone "Ideal" types that simply sound excellent and leave the stock version in the dust. These units include all of the wonderful effects you need at a quality that cant be beat! We love it and will be evaluating other models as well to be added to our mail in services in the coming weeks such as the AX8."