My issue with modding is simple-shipping and having my product in modders care, custody and control.
Not worth the hassle to me. Once my gear gets in my sound room safely - it stays there.
Insurance in shipping is very difficult to recover after a loss-ACV (actual cash value-value is depreciated, etc-and tough to just plain collect). And, never seen a modder offer to give customer a certificate of insurance showing they are covering component fully while on thier premises. If they did have coverage, it would still suffer depreciation. Imagine having an MR78, cost new - a few hundred dollars - value today maybe a grand and 20 years old. You would receive the original cost less 20 years worth of depreciation.
Just my thoughts.