I'm confused. Are you desiring to use it as a tape deck, to output music to your home hifi system?
If so, a real tape deck will perform better than any boombox. You can get a vintage tape deck on Ebay for only $100-200 that will play tapes better than any boombox.
Or do you want a boombox because of its style & portability?
On your list, I would avoid the RX-5150, it sounds weak.
The RX-5350 is huge & impressive, but it usually goes for $600+
I would look for an Aiwa TPR-950 or 955, it has a great sounding tape deck. It looks kind of small but it sounds fantastic. They usually go for $250-350 on Ebay.
The JVC M70 is also nice, but everyone else has one, and due to its popularity they are higher priced, usually $350-450