I personally own a RADAR II (Otari) and and a number of TASCAM products. I purchased a TASCAM SX1 that was released with a tremendous hype. It was supposed to be their flag ship digital recording solution. I must say that the SX1 is a hell of a rig and I really have liked it....BUT.... midstream TASCAM dropped the SX1 like a hot potatoe. TASCAM FAILED.... AND I SAY FAILED TO LIVE UP TO THEIR PROMISES. I still have the origional brochure that made the promises of what the SX1 would do. TASCAM stopped upgrading the software and they never did allow me to jump to 96K which was a big selling point for me. On the other hand TASCAM gear is relatively cheap and you get a pretty big bang for your buck. I am going to get a DV RA1000 but I think I know what to expect. TASCAM converters are very much consumer quality.
Now for RADAR. Though I purchased my RADAR in the olden days from Otari the folks at iZ have been stellar.... these guys set the gold standard for customer service. The RADAR converters are music to my ear.... I love em. Also, in the 8 years I have owned the RADAR it has NEVER crashed.. and I don't use the term NEVER lightly. The RADAR is the rock. I am considering upgrading to a RADAR SNyquist. I consider my time to be valuable and a downed machine eats any savings of getting the cheaper solution.
The only circumstances underwhich I would consider the TASCAM 48 is if I had a chance to spend a few days with one in full function. I would use my ear and learn exactly what it was capable to doing. I would absolutely not believe anything TEAC says or even prints regarding what is supposed to do.
Many people would consider RADAR converters to be upper class. If you add up the cost of 24 AD and DA converters that are upper class quality that just about equals the cost of a RADAR V. Not only can the RADAR stand on its own as a hard disc recorder but it can be linked directly to a DAW AES or TDIF and provide a front end of 24 great AD converters if you like to work inside of the box.
Keep in mind that the RADAR simply works as a recorder that allows one to edit. You get 24 and you get 24 out. No mixing inside of the box, no plugins, no automation, no EQ, no dynamics. With the TASCAM you get alot of hype.
If the TASCAM were anything more than vapor it would be out already. I think there must be problems with it because it was promised a long time ago. I don't think that they have hit the street yet.
Check out the the unoffical TASCAM forum
http://tascamforums.com/ and you can see there is a topic for the 48. The folks that frequent the Tascam forums are a great group and are the saving grace for the Tascam products.
Well, I guess I got that off my chest!