I would say stick with Win 98SE..and go to XP when its finished..they have an upcoming SR due in the fall of this year..whereas 98SE is done ! Win 2k will have SR3 this summer.
Im running 98SE and Win 2k in a dual boot scenario..and using the Motu 2408mk II..which has WDM drivers that work in both OS,s..
After performing the tweaks for both OS,s the difference between the two are....Latency of 1.5 in Win 2K..and 2.9 in Win 98SE..of course, the more tasks you try to perform the higher the latency has to be in order to carry out those functions..so the low end is only possible when youre doing practically nothing..
I am very pleased with the performance of the Motu and Win 98SE in this system at the present...I must mentioned that I am running a P4 1.6 Intel MB with the 850 chipset and 1054MB of RAMBUS..
The only prob I ever really had with 98SE in the past is the lock ups and/or freezes...but with the new horsepower it is actually quite stable and just as stable as Win 2K on my system anyway..Also, I must add that this is a music production computer only..nothing but multitracking and recording software on this machine..which of course I would recommend above all else..
build another for the internet and games and office and crap..
I also believe that Sonar 2 is a lot more stable than any of the previous by far..its running flawlessly under both OS,s. This may be contributing more than I suspect..
I am now optimizing the Delta 1010 under both OS,s and will report on that soon...
Oh , on the latency issue..latency is only a problem when it is interfering with what you are trying to do in realtime..in other words..you should be able to work with up to 25 ms latency on your realtime controllers ..make sense?...If you can peck the keys
and not hear the delay..then you are in the house
..if it is a problem..dont use input monitoring while recording..and make the adjustments in the DAW if needed..( which should not be the case).
The Strenghth of the WDM drivers are suppose to be
1. Be able to play your software synths in realtime while using realtime controllers..
2. Monitor effects while recording in realtime..
Neither are necessary to create stellar recordings as the past will certainly prove.
For the tweaks..go to Steinberg,s website..this was pretty comprehensive for XP and Win 2k..and Tascam for Win 98 was quite sufficient..
Good luck( and go Pentium)