Awesome features, but buggy.
I usually either review when I rave or when I rant, but this time I will do both.
Raves: Excellent User-interface (nice color scheme!), can support multiple monitors, love the 6 layout buttons, love the easy Automation, Track Folders (although nesting them would be even better), feels like a console should, but can switch easily to the waves/tracks views. I love the manual automation editing (i.e. Gain, Pan, VST automation editing etc.). The AudioSnap (manual methods) rocks! I love being able to clean up a bad drum hit or sloppy guitar chord etc. V-Vocal is very cool, but my V-Vocal doesn't work at all (bug?) Some of the plug-ins are very nice, but I tend to gravitate back to Waves plug-ins. Albeit, the Sonar plug-ins are free! Some of the other plug-ins are cool, like the Transient Shaper. But use your ears!! It can do more harm than good in some cases.
Rants: Buggy (I know Cakewalk doesn't want to leave that out there, and work hard not to give us bugs, but I have a song that simply will not finish exporting, even after processing for 12 hours), and has some Skylight bugs (cosmetic). It also runs like a bad 32-bit emulator in 64-bit Windows 7 instead of running like a true 64-bit native program (haven't tested OSX). there's a big learning curve.
Cakewalk over-emphasizes MIDI (which is just my perception). Audio Editing is absolutely HORRIBLE! Unless you know every single detail of every editing feature, this is among the most klunky and inflexible audio editors unless you aren't very good with manual editing and don't care about accuracy to the audio sample level. Some VERY basic editing features are missed in this program.
Pro-Channel is useful, but I found that external plug-ins were actually easier to use and I find myself more likely to use those over the ProChannel.
I love that Sonar comes packed with some great plug-ins, but I tend to use plug-ins from 3rd-party vendors more often than not. Besides, I cannot, for the life of me, figure out how to use the PerfectSpace Convolution Reverb. It makes absolutely no sense to me.
Delivery: Cakewalk believes in content and filling your plate with software (some of you may like that), which is probably why you still can't download your full copy of Sonar X1 Producer when you place your order. I would have preferred they dump the extra "junk", lessen the price and let me download Sonar X1. Or, at least, let me extend my Trial period with a "don't-kill-my-trial-license-while-I-wait-on-the-box to-show-up" feature.
Summary: I really like what Cakewalk has done here. I believe the company has gone to the pros and novices alike to find out what people really want and the price is actually good! There's some new features I wouldn't have considered possible (ala AudioSnap), and some I'll never use in a million years because there's really no good way to learn them (even with the offered training videos). I do recommend purchasing the Groove3 training videos: Explained and Tips and Tricks. I love the guy's voice, too (very ice-creamy).
But! Alas, Sonar X1 seems to be fraught with bugs (at least in my case (ver. X1c Build 319)), crashes frequently, freezes up, doesn't seem test for I/O speeds/capacity, seems to work better in Windows XP than 64-Bit Windows 7, and seems to "expire" processing a 3-minute song at 30 tracks, after 12 hours, even though I've cleared out AudioSnap and "Bounced to Clips", rendering my work at a standstill until Cakewalk can help me fix the issue--if there's a fix.
It seems more resources at CakeWalk are innovators and software programmers, but I gather there is some void left in the area of hardware driver integration expertise. Still, it's an awesome product and priced very well.