Right there with you. Same dilemma!
Needed a thinner TV than my Old Monstrosity (it's a technical term) asap due to a move, but I was still saving up for a flat panel. I found a KDF42WE655 with the blue blob/blue pixels issue on Craigslist for $50, and since I would mostly use it as a monitor and for kids' cartoons, I figured the brightness would mask the defects and it would be a good transitional TV--which it is.
Now I've come to really like this TV and I am thinking of attempting the $160 repair, but I am seriously concerned about the convergence issue. I really don't want to spend the $329 for a refurb because then I might as well get a newer, functional TV for a couple hundred bucks more. But I refuse to simply discard this one just because it has blue-blobitis, and think it'd be a fun project while I save up for the new set. I'm just afraid of making it unwatchable before I'm ready to let it go!
I'm curious to find out if you ended up going the total DIY, trial-and-error $160 route. Hope you post an update!