Japanese Luxman Integrated Amps

my Japanese 505 - flawless, sold it within 1 day, (multiple offers) to upgrade to the 550. I believe my converter failed with the 550 after about a year but not sure   but the unit wouldn’t turn on. 
I sent it to George Meyer in LA for repair.  They said that it was a Luxman fault not the converter. Then UPS lost it on its way back to me.😫

I purchased the 550 new off Eb.. for $3800 including import fees. 

repair and shipping to GM =$1100 = $4900 vs 7K new.

I would definitely buy another Japanese version but use a higher quality converter. 

I gotta say that it took a while to find a tech that could work on it here in the states.

I also saw on another resale site that they were able to convert a 100 v to 120 on a 505 but it couldn’t be done on the 550.

Luxman explicitly states they won’t service products mfg elsewhere. So no warranty.

I moved 4 times between Europe and the US with hi-fi gear and used basic (but not cheapest junk) converters without any problem for decades.

Exactly, as grizzly said: basic, just not cheap junk. 

I went with a small lightweight one at the end of a cord. It has zero hum, fits easily anywhere, i.e. right behind my turntable. I plug my 100v turntable into it, and plug it into the wall outlet several feet away.

My biggest concern is forgetting the TT is 100 v and forgetting the transformer, which is why mine is just behind the TT where I can see/be reminded of it.

IF you think, I'm gonna get a bigger one just to be sure, then think about it's weight and location, the bigger the more unnecessary heat, and ...

i don't know, is there more hum potential of larger ones?