I have heard the MBL 1611 F a few years ago and the Lampizator BIG 7 more recently. Impossible for me to give you any differences in sonic impressions.
Dac tech has been moving quickly. The MBL 1611 F is very long in tooth (2011-12?). I can't find any reference to what underlying DAC chip it is using in this model, but previous models used off the shelf DAC chips with additional filters added/built by MBL which I assume still remains the same. The problem is that the MBL1611F doesn't support any of the higher rez PCM and even worse, no DSD. It still remains a beautiful piece of equipment, but I would think a more modern DAC with similar capabilities to GG would be a better comparison.
To give you an idea, I ended up with GG after some comparisons. I also own a PS Audio DirectStream. Interestingly here is a review that does some comparisons between DirectStream and MBL1611F. (
http://www.positive-feedback.com/Issue74/psaudio_directstream.htm). If I was you, I would do comparison shopping between GG and totaldac and high end Delta Sigma DAC (many to choose from). For me, if you appreciate the magic of DHT in output stage of DAC and like the versatility of voicing the DAC via tubes, the GG is the top choice.