I read all these mower reviews and just want to repower my 42" Murray widebody. $600 for a 20HP V-twin delivered and may have to play with the muffler (needs an above deck one). There is 1" flex pipe and plenty of single mufflers around for each side.
1) Only needed safety switches, batteries and starters. Never issues with the deck or mowing (one a decade the belt wears out). Original spindles work great, spin quiet, grease them every year.
2) Peerless trans had a loose internal bolt after 15 years(I read this is an issue with some Deere). Took it apart, red locktite, resealed, no problems. Got 20W50 and 80W90. A local repair place said the repower on that Murray will give you less headaches than some new big box mowers. Said he has plenty in the back in for repair. Told me the trans on cheap mowers now are garbage, no where near the peerless automatic quality. He said unless you want to spend 4 grand +, repower should be a consideration. He offered me 200 for it with the bagger.