It's interesting to note that one of Walter's first customers (circa early 1970's) was the pop group The Carpenters, who bought some WW amps to take on tour for use on guitar, bass guitar and keyboards. WW amps were not just intended for DB. One of the first upright bassists to use a WW amp was Herb Mickman.
Yes, my Ultra sounds great for anything you plug into it, really. You just need to understand the eq and use your ears!
Since the OP was asking about affordable alternatives to WW...yes, since Pattitucci is a long time user of WW, and now uses and endorses the Aguilar TH500, and after auditioning it myself, I feel good about recommending it to him. It's a quality piece using quality components in the build. It isn't a WW, but it's a damn solid piece.
For myself, the discussion of the Demeter Minnie here has got me checking it out more closely..
I own the original '80's Demeter tube pre that the Minne is based on. Great design, medium build quality, I had to get things re soldered to make it dependable. The components and design are great, but assembling quality medium. I had the same problem with the original Demeter tube DI as well as a couple of his pedals. Demeter didn't even have UL status until the early '90's or so...these pieces came with 2 prong plugs!
The new Minnie looks really great, and I hear the problems with assembling quality are past. I hope to purchase one soon! Very soon.