Unforunately, I cannot really answer your survey because my custom tank experience was not too good. So i'll share in this comment.
I had a relatively small custom tank built by Crystal Dynamics using clear silicone. The tank I received first had some very unacceptable build issues that brought me to question their entire quality check system. How can a glass pane not be machine polished and left with the cut marks, especially on a custom rimless tank. Not to mention major scratches. I had a new tank built at no cost, but this meant me having to haul the tank back into my car, drive 8 hours total to their shop and back home to pick up the new tank. The new tank looked better (relatively speaking) so I accepted it. But this one also had issues, this time with marring or imperfections between the bottom pane and reinforcement material. I have a bare bottom so I can see if every day until coraline algae covers it (looks like spilled liquid on a table). I don't know what the excuse is here... If a smaller tank means less profits for them, just charge me more instead of giving me lower quality product. If clear silicone is hard to use then tell me it's a non-negotiable 'no'. If 3/8" glass require machines to be re-adjusted, then just charge me more to get it readjusted right. I cannot speak of the quality produced by Crystal Dynamics for larger tanks with black silicone but for my tank, it was not that great. I had an ELOS tank at some point in life and while the custom tank would cost an arm and a leg, it probably would have been worth it to shell out the extra $$$$ for the Custom Elos tank since I look at the tank every single day. A nice controller and sump sits inside the stand cover and fancy pumps get covered in algae anyways so why did I skimp on the display tank (who knows... lesson learned).
Manufacturer: Crystal Dynamics
Date of Deposit Paid: Beginning of December 2018
Tank Size: 30"x25"x12"
Silicone: Clear
Overflow: Modular Marine, provided by me
Cost: ~$800 without shipping
Date of First Tank Completion: Early/Mid February 2019
Issues: Unfinished/polishes edges on starphire glass, scratches on glass panel towards the bottom where the reinforced black ABS material was placed.
Resolution: A new tank was build and I returned the first tank
Date of Second Tank Completion: Late March 2019
New Issues: There are large areas of imperfection between where the bottom glass pane meets the reinforced black ABS material, which is an eye sore since my tank is bare bottom and one of the viewable glass panes was siliconed ever so slightly angeled such that the glass pane is not siliconed at a 90 degree angle
Communication of Manufacturer: decent. They were responsive but sometimes required multiple follow ups to solicit a response
Conclusion: Steer clear of this one and pay the extra premium for a custom Elos tank (I anecdotally heard Reef Savvy is