igiwigi
Cubase has Sys ex support for keyboard players to get their onboard sounds sequencing nice.
This implies that unless you have Sysex support you cannot get your external keyboards sequencing nice which of course is not true at all. I have got 8 external synths and with Studio One trust me I am getting everything sequencing nice!
Sysex only allows you to dump sounds into your synths on the fly and edit them on the fly which is not something you always have to do. If you are someone who either creates patches or edits them, then you can still do this with Studio One and just sequence the final sound you end up with. One of my synths is a Roland JD800 and I can easily edit patches on the fly as well manually while Studio One is sequencing it.
You can use an editor program for your synths and often the editors use Sysex to communicate with the synths. Studio One allows you to run an editor tandem with Studio One itself i.e. the editor and Studio One can address the same synth at the same time.
Sysex support (or lack of) alone is not enough reason to not even consider a DAW. Studio One for some may be a million times better and nicer than Cubase. Many Cubase users have migrated to Studio One in fact.
The real trick in a migration plan is be prepared to learn a new DAW. Many here are ranting that they will never be able to do it but that is not true. After 6 months of learning a new DAW and using it you will be just as fluent as you were in Sonar. You will totally forget Sonar and basically never look back. The human brain is pretty powerful. Stop underestimating it.
It gets back to the power of your subconscious mind. Keep telling yourself that you will never be able to learn a new DAW as well as you know Sonar and then you never will. Start sending the right messages into your subconscious instead which is I can and will learn a new DAW and I will be as good as I ever was in Sonar or better. You might just surprise yourself.