Upgrading Quicksilver preamp or amp caps -- warranty impact?

@decooney 

Removed the factory installed affordable and reliable $5.95 Orange Drop caps (used a lot in guitars) originally insatalled in my Mono 120 amps and replaced them with $50ea (2 per amp) Mundorf Capacitor 0.22uF 1000Vdc MCap® Supreme EVO SilverGold Black SESG (non-oil) version. Same microfarad, and higher voltage capacity.

This makes a lot of sense. Is it possible that QS uses a $5.95 cap because it's the best one for the design? It's possible but not probable. He's making an amp to a price point. The tubes in my QS preamp were $12 each. Replacing them made a big difference.

Paul McGowan discusses this issue in (at least) two videos.

https://youtu.be/bq5Ph2ySlD8
https://youtu.be/mpqUsEAk39g

If I were a mainstream mfg, I too would likely focus on Reliability, Availability, and Cost to stay in business. All key factors. As long as the "standard" version lasts and sounds "good enough" for 95% of the mainstream consumers, it keeps variation away, keeps costs down, and makes the product more affordable for consumers. Makes good business sense. Let the other 5% of DIY’ers do what they want to do and take on the risk themselves, etc etc. Less headaches for the manufacturer. It also comes down to those who want upgraded vs. standard. Standard works fine. And, sometimes changes or upgrades don’t always work better, fwiw.

as mentioned, the manufacturers can not afford to install high end copper foil caps, they retail price increase would just be too much. Also if you want to go further, replace the bias and plate load resistors with wire wound. will make the amp much quieter, and let more micro detail come through. But again, not cheap.

@hilde45 I have reached out to Mike recently about using lower gain tubes and have not as yet heard back. 
Let us know if you do. 
P.S. I may be putting my current version of his Line Stage Preamp up for sale soon as it’s not a good fit for my system.

@johnss My system is very, very quiet. I guess units can differ.
@gochurchgo If you put your line stage up for sale, I bet it goes quickly!