
I'll be buying Cubase as soon as the crossgrade from PT becomes available in the US.
CUBASE VS.PRO TOOLS PRO
Those using Macs with Pro Tools seem to be much happier than those using PCs - especially with "third party interfaces" (like me). I don't regret choosing Pro Tools, but knowing what I know now I would at least look seriously at alternatives before committing to a package that one must accept as being "not like other software." Since you're already travelling in Steinberg circles, it may be easier for you to start using Nuendo than to learn a new system from scratch. That was a few years ago so things may have changed somewhat, but I'm sure the point that Nuendo is a viable alternative still stands. I haven't taken anything more than a cursory look at any other DAW since I switched from SAW to Pro Tools about 200 years ago (in DAW years) so I can't offer any opinions on relative workflows, but a trusted co-worker who shares the Pro Tools system with me at work but uses Nuendo for his own side projects once told me that he felt Nuendo had an edge over Pro Tools in the form of a few convenience features Pro Tools lacked. With Pro Tools, your eligibility for future upgrades requires a commitment to perpetual payment.
CUBASE VS.PRO TOOLS SOFTWARE
Things that have no effect on other software can cripple Pro Tools. It can be rendered unusable by things like certain video cards, USB drivers, even some Intel CPUs. Pro Tools seems to be written in a way that makes it very sensitive to its environment. Nuendo does not require that you purchase specific hardware. That's not a bad thing - there's nothing wrong with their hardware - but it does limit your choices, and puts the price of entry at $5000 minimum. That means buying into Avid's hardware too.

You mentioned that you would like to use Pro Tools HD. I know this doesn't address your question, but as a long-time Pro Tools user I can tell you that if I were in the position you are now, I would give really serious consideration to going with Nuendo instead of Pro Tools. On a scale 1-10 of mastering Cubase I'm at like an 8.maybe 8.3 lol but I'm just questionable about the switch
CUBASE VS.PRO TOOLS PLUS
Plus I wanted to use Pro Tools HD unless Cubase has something similar. I make all of my beats in Cubase via kontakt, massive, and battery and lately have been wondering how much different/similar are Cubase and pro tools. I want to switch because in a few years (3-5 I guess.) I want to have my own professional recording studio. (Presonus has been known to abandon products) Just waiting to see what happens support wise over time. Studio One is also pretty neat and cost effective.

They are also more advanced as far as file organization. If you are into the midi side of things, I think Cubase/Logic/Nuendo is a better way to go. I prefer Protools for large mix projects as it is more analogous to a console than a lot of other DAWs.

It just seemed like there were always more widows to migrate through and things to push. We used Cubase years ago and never really liked it.
