Re: Need info on Fender Blues Junior Amps....
I can't speak directly about the Blues Jr. but I have a Pro Jr., which is similar in many respects. I find the background hum that characterizes most of these amps objectionable, especially for recording -- all of my vintage amps from the 50'-70's are much quieter at idle, as is my 2003 Orange AD15/12. The PJ has been in and out of the shop for months to deal with unacceptable levels of hum. It seems to eat 12AX7 tubes at an alarming rate. The tone is very nice o/a, but can be a bit boxy -- a Princeton size cab is a much better fit for a 10" speaker IMO, let alone a 12".
All in all, for $300-400 or so (new) the Jr's aren't bad, but there are far better buys in low-power vintage amps (e.g., silverface Fenders, tweed and blonde Gibsons) for about the same money. The Orange AD15 (now discontinued) blows it away, albeit at about 3 times the price, but so does the Traynor YCV-20 for only about $100 more. If your tweeds are repros that you don't mind taking out of the house, then I doubt that you would find much use for the Jrs.