I would not call the 450D or 7200 a modern DSP radio. You cannot put IF DSP in a radio for 1000 bucks or so today and make it worth a crap
...to get good IF DSP you need at least a 590, K3 or 7410 not a 450
For the original authors sake, I want to point out that I think you are comparing different receiver architectures that use DSP in one IF stage to define the passband. What primarily makes up the performance difference, and cost, between the radios being compared is a "narrow" 1st IF filter before the DSP There are some differences in tone and filter shape when comparing an analog receiver/wide 1st IF filter to a DSP based receiver/wide IF filter but I think most people would prefer an IF-DSP system for the versatility it offers in both transmit and receive--even in a $1k radio.
...would not recommend a 2000 because while it does a lot of things it does not do any of them well because the IF DSP technology is is based on is very primitive and VERY dated
The receiver of the TS-2000 does not top the charts in dynamic range and it has some quarks but I would not attribute any of these weaknesses to an outdated IF DSP, but rather to the cheap ceramic filters in other analog filter stages (it is a common mod to replace some with good crystal filters). It really is a remarkably performing radio for everything it does though. The stock receiver performance is sufficient for the average station using wire antenna's on HF and small yagis on VHF/UHF (where the antenna gain is not enough to fill the band with strong stations).
This is a whole separate topic but it is interesting how many posts there are related to not being able to notice the difference while switching between 1st IF filters in new radios. Many have became sold that their receiver will melt without a narrow "roofing filter" but the truth is that very few stations really need the extra dynamic range they offer.